diff --git a/LanMountainDesktop.Launcher/AppJsonContext.cs b/LanMountainDesktop.Launcher/AppJsonContext.cs
index 57e6ac7..495e3f8 100644
--- a/LanMountainDesktop.Launcher/AppJsonContext.cs
+++ b/LanMountainDesktop.Launcher/AppJsonContext.cs
@@ -34,6 +34,7 @@ namespace LanMountainDesktop.Launcher;
 [JsonSerializable(typeof(PendingUpgrade))]
 [JsonSerializable(typeof(List<PendingUpgrade>))]
 [JsonSerializable(typeof(OobeStateFile))]
+[JsonSerializable(typeof(DataLocationConfig))]
 [JsonSerializable(typeof(GitHubRelease))]
 [JsonSerializable(typeof(GitHubAsset))]
 [JsonSerializable(typeof(List<GitHubRelease>))]
diff --git a/LanMountainDesktop.Launcher/Models/DataLocationModels.cs b/LanMountainDesktop.Launcher/Models/DataLocationModels.cs
new file mode 100644
index 0000000..89cad9b
--- /dev/null
+++ b/LanMountainDesktop.Launcher/Models/DataLocationModels.cs
@@ -0,0 +1,23 @@
+namespace LanMountainDesktop.Launcher.Models;
+
+internal enum DataLocationMode
+{
+    System,
+    Portable
+}
+
+internal sealed class DataLocationConfig
+{
+    public string DataLocationMode { get; set; } = "System";
+
+    public string? SystemDataPath { get; set; }
+
+    public string? PortableDataPath { get; set; }
+}
+
+internal sealed class DataLocationPromptResult
+{
+    public DataLocationMode SelectedMode { get; init; }
+
+    public bool MigrateExistingData { get; init; }
+}
diff --git a/LanMountainDesktop.Launcher/Services/DataLocationOobeStep.cs b/LanMountainDesktop.Launcher/Services/DataLocationOobeStep.cs
new file mode 100644
index 0000000..1abf73d
--- /dev/null
+++ b/LanMountainDesktop.Launcher/Services/DataLocationOobeStep.cs
@@ -0,0 +1,67 @@
+using Avalonia.Threading;
+using LanMountainDesktop.Launcher.Models;
+using LanMountainDesktop.Launcher.Views;
+
+namespace LanMountainDesktop.Launcher.Services;
+
+internal sealed class DataLocationOobeStep : IOobeStep
+{
+    private readonly DataLocationResolver _resolver;
+
+    public DataLocationOobeStep(DataLocationResolver resolver)
+    {
+        _resolver = resolver;
+    }
+
+    public async Task RunAsync(CancellationToken cancellationToken)
+    {
+        cancellationToken.ThrowIfCancellationRequested();
+
+        var existingConfig = _resolver.LoadConfig();
+        if (existingConfig is not null)
+        {
+            Logger.Info("DataLocation OOBE step skipped: config already exists.");
+            return;
+        }
+
+        DataLocationPromptWindow? window = null;
+        await Dispatcher.UIThread.InvokeAsync(() =>
+        {
+            window = new DataLocationPromptWindow(_resolver);
+            window.Show();
+        });
+
+        if (window is null)
+        {
+            Logger.Warn("DataLocation OOBE step failed: window could not be created.");
+            return;
+        }
+
+        try
+        {
+            var result = await window.WaitForChoiceAsync().ConfigureAwait(false);
+            if (result is null)
+            {
+                Logger.Info("DataLocation OOBE step: user cancelled or closed window. Using default system location.");
+                _resolver.ApplyLocationChoice(DataLocationMode.System, false);
+            }
+            else
+            {
+                var success = _resolver.ApplyLocationChoice(result.SelectedMode, result.MigrateExistingData);
+                Logger.Info(
+                    $"DataLocation OOBE step: user selected '{result.SelectedMode}'. " +
+                    $"Migrate={result.MigrateExistingData}; Success={success}.");
+            }
+        }
+        finally
+        {
+            await Dispatcher.UIThread.InvokeAsync(() =>
+            {
+                if (window.IsVisible)
+                {
+                    window.Close();
+                }
+            });
+        }
+    }
+}
diff --git a/LanMountainDesktop.Launcher/Services/DataLocationResolver.cs b/LanMountainDesktop.Launcher/Services/DataLocationResolver.cs
new file mode 100644
index 0000000..ae82021
--- /dev/null
+++ b/LanMountainDesktop.Launcher/Services/DataLocationResolver.cs
@@ -0,0 +1,244 @@
+using System.Text.Json;
+using LanMountainDesktop.Launcher.Models;
+
+namespace LanMountainDesktop.Launcher.Services;
+
+internal sealed class DataLocationResolver
+{
+    private const string ConfigFileName = "data-location.config.json";
+    private const string PortableDataFolderName = "AppData";
+
+    private readonly string _appRoot;
+    private readonly string _configPath;
+    private readonly string _defaultSystemDataPath;
+
+    public DataLocationResolver(string appRoot)
+    {
+        _appRoot = Path.GetFullPath(appRoot);
+        _configPath = Path.Combine(_appRoot, ConfigFileName);
+        _defaultSystemDataPath = Path.Combine(
+            Environment.GetFolderPath(Environment.SpecialFolder.LocalApplicationData),
+            "LanMountainDesktop");
+    }
+
+    public string AppRoot => _appRoot;
+
+    public string ConfigPath => _configPath;
+
+    public string DefaultSystemDataPath => _defaultSystemDataPath;
+
+    public string DefaultPortableDataPath => Path.Combine(_appRoot, PortableDataFolderName);
+
+    public bool IsPortableModeAllowed()
+    {
+        try
+        {
+            var testFile = Path.Combine(_appRoot, $".write-test-{Guid.NewGuid():N}.tmp");
+            File.WriteAllText(testFile, string.Empty);
+            File.Delete(testFile);
+            return true;
+        }
+        catch
+        {
+            return false;
+        }
+    }
+
+    public DataLocationConfig? LoadConfig()
+    {
+        try
+        {
+            if (!File.Exists(_configPath))
+            {
+                return null;
+            }
+
+            var json = File.ReadAllText(_configPath);
+            return JsonSerializer.Deserialize(json, AppJsonContext.Default.DataLocationConfig);
+        }
+        catch (Exception ex)
+        {
+            Logger.Warn($"Failed to load data location config from '{_configPath}'. Error='{ex.Message}'.");
+            return null;
+        }
+    }
+
+    public bool SaveConfig(DataLocationConfig config)
+    {
+        try
+        {
+            var json = JsonSerializer.Serialize(config, AppJsonContext.Default.DataLocationConfig);
+            File.WriteAllText(_configPath, json);
+            return true;
+        }
+        catch (Exception ex)
+        {
+            Logger.Warn($"Failed to save data location config to '{_configPath}'. Error='{ex.Message}'.");
+            return false;
+        }
+    }
+
+    public string ResolveDataRoot()
+    {
+        var config = LoadConfig();
+        if (config is null)
+        {
+            return _defaultSystemDataPath;
+        }
+
+        if (string.Equals(config.DataLocationMode, "Portable", StringComparison.OrdinalIgnoreCase))
+        {
+            var portablePath = !string.IsNullOrWhiteSpace(config.PortableDataPath)
+                ? config.PortableDataPath
+                : DefaultPortableDataPath;
+            return Path.GetFullPath(portablePath);
+        }
+
+        return !string.IsNullOrWhiteSpace(config.SystemDataPath)
+            ? Path.GetFullPath(config.SystemDataPath)
+            : _defaultSystemDataPath;
+    }
+
+    public DataLocationMode ResolveMode()
+    {
+        var config = LoadConfig();
+        if (config is null)
+        {
+            return DataLocationMode.System;
+        }
+
+        return string.Equals(config.DataLocationMode, "Portable", StringComparison.OrdinalIgnoreCase)
+            ? DataLocationMode.Portable
+            : DataLocationMode.System;
+    }
+
+    public bool HasExistingSystemData()
+    {
+        var systemPath = _defaultSystemDataPath;
+        if (!Directory.Exists(systemPath))
+        {
+            return false;
+        }
+
+        var markerFiles = new[]
+        {
+            Path.Combine(systemPath, "settings.json"),
+            Path.Combine(systemPath, "launcher-settings.json"),
+            Path.Combine(systemPath, "component-state.db"),
+            Path.Combine(systemPath, "app.db")
+        };
+
+        return markerFiles.Any(File.Exists);
+    }
+
+    public bool ApplyLocationChoice(DataLocationMode mode, bool migrateExistingData)
+    {
+        var config = new DataLocationConfig
+        {
+            DataLocationMode = mode.ToString(),
+            SystemDataPath = _defaultSystemDataPath,
+            PortableDataPath = DefaultPortableDataPath
+        };
+
+        if (!SaveConfig(config))
+        {
+            return false;
+        }
+
+        var targetDataRoot = mode == DataLocationMode.Portable
+            ? DefaultPortableDataPath
+            : _defaultSystemDataPath;
+
+        try
+        {
+            Directory.CreateDirectory(targetDataRoot);
+        }
+        catch (Exception ex)
+        {
+            Logger.Warn($"Failed to create data directory '{targetDataRoot}'. Error='{ex.Message}'.");
+            return false;
+        }
+
+        if (migrateExistingData && mode == DataLocationMode.Portable)
+        {
+            MigrateSystemDataToPortable();
+        }
+
+        return true;
+    }
+
+    private void MigrateSystemDataToPortable()
+    {
+        if (!HasExistingSystemData())
+        {
+            return;
+        }
+
+        var sourcePath = _defaultSystemDataPath;
+        var targetPath = DefaultPortableDataPath;
+
+        try
+        {
+            Directory.CreateDirectory(targetPath);
+
+            var filesToMigrate = Directory.GetFiles(sourcePath, "*", SearchOption.TopDirectoryOnly);
+            foreach (var file in filesToMigrate)
+            {
+                var fileName = Path.GetFileName(file);
+                var destFile = Path.Combine(targetPath, fileName);
+                try
+                {
+                    File.Copy(file, destFile, overwrite: true);
+                }
+                catch (Exception ex)
+                {
+                    Logger.Warn($"Failed to migrate file '{fileName}'. Error='{ex.Message}'.");
+                }
+            }
+
+            var dirsToMigrate = Directory.GetDirectories(sourcePath, "*", SearchOption.TopDirectoryOnly);
+            foreach (var dir in dirsToMigrate)
+            {
+                var dirName = Path.GetFileName(dir);
+                if (string.Equals(dirName, ".launcher", StringComparison.OrdinalIgnoreCase) &&
+                    string.Equals(Path.GetFileName(sourcePath), "LanMountainDesktop", StringComparison.OrdinalIgnoreCase))
+                {
+                    continue;
+                }
+
+                var destDir = Path.Combine(targetPath, dirName);
+                try
+                {
+                    CopyDirectory(dir, destDir);
+                }
+                catch (Exception ex)
+                {
+                    Logger.Warn($"Failed to migrate directory '{dirName}'. Error='{ex.Message}'.");
+                }
+            }
+
+            Logger.Info($"Data migration completed. Source='{sourcePath}'; Target='{targetPath}'.");
+        }
+        catch (Exception ex)
+        {
+            Logger.Warn($"Data migration failed. Source='{sourcePath}'; Target='{targetPath}'. Error='{ex.Message}'.");
+        }
+    }
+
+    private static void CopyDirectory(string sourceDir, string destDir)
+    {
+        Directory.CreateDirectory(destDir);
+
+        foreach (var file in Directory.GetFiles(sourceDir))
+        {
+            var destFile = Path.Combine(destDir, Path.GetFileName(file));
+            File.Copy(file, destFile, overwrite: true);
+        }
+
+        foreach (var subDir in Directory.GetDirectories(sourceDir))
+        {
+            var destSubDir = Path.Combine(destDir, Path.GetFileName(subDir));
+            CopyDirectory(subDir, destSubDir);
+        }
+    }
+}
diff --git a/LanMountainDesktop.Launcher/Services/HostLaunchPlan.cs b/LanMountainDesktop.Launcher/Services/HostLaunchPlan.cs
index 2b7d7d7..ce01a88 100644
--- a/LanMountainDesktop.Launcher/Services/HostLaunchPlan.cs
+++ b/LanMountainDesktop.Launcher/Services/HostLaunchPlan.cs
@@ -12,10 +12,12 @@ internal sealed record HostLaunchPlan(
 
 internal static class HostLaunchPlanBuilder
 {
+    public const string DataRootOptionName = "data-root";
+
     private static readonly string[] LauncherOnlyOptions =
     [
         "debug", "show-loading-details", "plugins-dir", "source", "result",
-        "app-root",
+        "app-root", DataRootOptionName,
         LauncherIpcConstants.LauncherPidEnvVar,
         LauncherIpcConstants.PackageRootEnvVar,
         LauncherIpcConstants.VersionEnvVar,
@@ -25,7 +27,8 @@ internal static class HostLaunchPlanBuilder
     public static HostLaunchPlan Build(
         CommandContext context,
         DeploymentLocator deploymentLocator,
-        HostResolutionResult resolution)
+        HostResolutionResult resolution,
+        string? dataRoot = null)
     {
         ArgumentNullException.ThrowIfNull(context);
         ArgumentNullException.ThrowIfNull(deploymentLocator);
@@ -39,7 +42,7 @@ internal static class HostLaunchPlanBuilder
         var hostPath = Path.GetFullPath(resolution.ResolvedHostPath);
         var packageRoot = ResolvePackageRoot(hostPath, resolution.AppRoot, resolution.ResolutionSource);
         var versionInfo = deploymentLocator.GetVersionInfo();
-        var arguments = BuildForwardedArguments(context, packageRoot, versionInfo);
+        var arguments = BuildForwardedArguments(context, packageRoot, versionInfo, dataRoot);
         var environment = new Dictionary<string, string>(StringComparer.OrdinalIgnoreCase)
         {
             [LauncherIpcConstants.LauncherPidEnvVar] = Environment.ProcessId.ToString(),
@@ -48,6 +51,11 @@ internal static class HostLaunchPlanBuilder
             [LauncherIpcConstants.CodenameEnvVar] = versionInfo.Codename
         };
 
+        if (!string.IsNullOrWhiteSpace(dataRoot))
+        {
+            environment["LMD_DATA_ROOT"] = dataRoot;
+        }
+
         return new HostLaunchPlan(
             hostPath,
             packageRoot,
@@ -92,7 +100,8 @@ internal static class HostLaunchPlanBuilder
     private static IReadOnlyList<string> BuildForwardedArguments(
         CommandContext context,
         string packageRoot,
-        AppVersionInfo versionInfo)
+        AppVersionInfo versionInfo,
+        string? dataRoot = null)
     {
         var arguments = new List<string>();
 
@@ -144,6 +153,11 @@ internal static class HostLaunchPlanBuilder
         arguments.Add($"--{LauncherIpcConstants.VersionEnvVar}={versionInfo.Version}");
         arguments.Add($"--{LauncherIpcConstants.CodenameEnvVar}={versionInfo.Codename}");
 
+        if (!string.IsNullOrWhiteSpace(dataRoot))
+        {
+            arguments.Add($"--{DataRootOptionName}={dataRoot}");
+        }
+
         return arguments;
     }
 
diff --git a/LanMountainDesktop.Launcher/Services/LauncherDebugSettingsStore.cs b/LanMountainDesktop.Launcher/Services/LauncherDebugSettingsStore.cs
index 5cb0bed..6ea9d68 100644
--- a/LanMountainDesktop.Launcher/Services/LauncherDebugSettingsStore.cs
+++ b/LanMountainDesktop.Launcher/Services/LauncherDebugSettingsStore.cs
@@ -100,6 +100,16 @@ internal static class LauncherDebugSettingsStore
 
     private static string ResolveConfigBaseDirectory()
     {
+        try
+        {
+            var appRoot = Commands.ResolveAppRoot(CommandContext.FromArgs([]));
+            var resolver = new DataLocationResolver(appRoot);
+            return Path.Combine(resolver.ResolveDataRoot(), ".launcher");
+        }
+        catch
+        {
+        }
+
         try
         {
             var appData = Environment.GetFolderPath(Environment.SpecialFolder.LocalApplicationData);
diff --git a/LanMountainDesktop.Launcher/Services/LauncherFlowCoordinator.cs b/LanMountainDesktop.Launcher/Services/LauncherFlowCoordinator.cs
index a17558b..c598042 100644
--- a/LanMountainDesktop.Launcher/Services/LauncherFlowCoordinator.cs
+++ b/LanMountainDesktop.Launcher/Services/LauncherFlowCoordinator.cs
@@ -23,6 +23,7 @@ internal sealed class LauncherFlowCoordinator
     private readonly PluginInstallerService _pluginInstallerService;
     private readonly StartupAttemptRegistry _startupAttemptRegistry;
     private readonly LauncherCoordinatorIpcServer? _coordinatorIpcServer;
+    private readonly DataLocationResolver _dataLocationResolver;
     private readonly IReadOnlyList<IOobeStep> _oobeSteps;
 
     public LauncherFlowCoordinator(
@@ -41,7 +42,12 @@ internal sealed class LauncherFlowCoordinator
         _pluginInstallerService = pluginInstallerService;
         _startupAttemptRegistry = startupAttemptRegistry ?? new StartupAttemptRegistry();
         _coordinatorIpcServer = coordinatorIpcServer;
-        _oobeSteps = [new WelcomeOobeStep(_oobeStateService, _context)];
+        _dataLocationResolver = new DataLocationResolver(deploymentLocator.GetAppRoot());
+        _oobeSteps =
+        [
+            new WelcomeOobeStep(_oobeStateService, _context),
+            new DataLocationOobeStep(_dataLocationResolver)
+        ];
     }
 
     public static string ResolveSuccessPolicyKey(CommandContext context)
@@ -1025,7 +1031,8 @@ internal sealed class LauncherFlowCoordinator
         bool forceDirectMode,
         string? retryTag)
     {
-        var plan = HostLaunchPlanBuilder.Build(_context, _deploymentLocator, resolution);
+        var dataRoot = _dataLocationResolver.ResolveDataRoot();
+        var plan = HostLaunchPlanBuilder.Build(_context, _deploymentLocator, resolution, dataRoot);
         var hostPath = plan.HostPath;
         if (OperatingSystem.IsLinux() || OperatingSystem.IsMacOS())
         {
diff --git a/LanMountainDesktop.Launcher/Services/Logger.cs b/LanMountainDesktop.Launcher/Services/Logger.cs
index 5d60c39..0e474a9 100644
--- a/LanMountainDesktop.Launcher/Services/Logger.cs
+++ b/LanMountainDesktop.Launcher/Services/Logger.cs
@@ -53,6 +53,16 @@ internal static class Logger
     /// </summary>
     private static string? GetLogDirectory()
     {
+        try
+        {
+            var appRoot = Commands.ResolveAppRoot(CommandContext.FromArgs([]));
+            var resolver = new DataLocationResolver(appRoot);
+            return Path.Combine(resolver.ResolveDataRoot(), ".launcher", "logs");
+        }
+        catch
+        {
+        }
+
         try
         {
             var appData = Environment.GetFolderPath(Environment.SpecialFolder.LocalApplicationData);
diff --git a/LanMountainDesktop.Launcher/Services/OobeStateService.cs b/LanMountainDesktop.Launcher/Services/OobeStateService.cs
index 6903ba2..39c8f03 100644
--- a/LanMountainDesktop.Launcher/Services/OobeStateService.cs
+++ b/LanMountainDesktop.Launcher/Services/OobeStateService.cs
@@ -21,7 +21,7 @@ internal sealed class OobeStateService
         _executionSnapshot = executionSnapshot ?? LauncherExecutionContext.Capture();
 
         var stateRoot = string.IsNullOrWhiteSpace(stateRootOverride)
-            ? GetDefaultStateRoot()
+            ? ResolveStateRoot(appRoot)
             : Path.GetFullPath(stateRootOverride);
         _stateDirectory = Path.Combine(stateRoot, ".launcher", "state");
         _statePath = Path.Combine(_stateDirectory, "oobe-state.json");
@@ -208,14 +208,22 @@ internal sealed class OobeStateService
         };
     }
 
-    private static string GetDefaultStateRoot()
+    private static string ResolveStateRoot(string appRoot)
     {
-        var appData = Environment.GetFolderPath(Environment.SpecialFolder.LocalApplicationData);
-        if (string.IsNullOrWhiteSpace(appData))
+        try
         {
-            throw new InvalidOperationException("LocalApplicationData is unavailable.");
+            var resolver = new DataLocationResolver(appRoot);
+            return resolver.ResolveDataRoot();
         }
+        catch
+        {
+            var appData = Environment.GetFolderPath(Environment.SpecialFolder.LocalApplicationData);
+            if (string.IsNullOrWhiteSpace(appData))
+            {
+                throw new InvalidOperationException("LocalApplicationData is unavailable.");
+            }
 
-        return Path.Combine(appData, "LanMountainDesktop");
+            return Path.Combine(appData, "LanMountainDesktop");
+        }
     }
 }
diff --git a/LanMountainDesktop.Launcher/Services/PluginInstallerService.cs b/LanMountainDesktop.Launcher/Services/PluginInstallerService.cs
index 905fe97..60beff7 100644
--- a/LanMountainDesktop.Launcher/Services/PluginInstallerService.cs
+++ b/LanMountainDesktop.Launcher/Services/PluginInstallerService.cs
@@ -63,13 +63,28 @@ internal sealed class PluginInstallerService
             return null;
         }
 
-        var localAppData = Environment.GetFolderPath(Environment.SpecialFolder.LocalApplicationData);
-        if (string.IsNullOrWhiteSpace(localAppData))
+        string? allowedRoot = null;
+        try
+        {
+            var appRoot = Commands.ResolveAppRoot(CommandContext.FromArgs([]));
+            var resolver = new DataLocationResolver(appRoot);
+            allowedRoot = EnsureTrailingSeparator(resolver.ResolveDataRoot());
+        }
+        catch
         {
-            return null;
         }
 
-        var allowedRoot = EnsureTrailingSeparator(Path.Combine(Path.GetFullPath(localAppData), "LanMountainDesktop"));
+        if (string.IsNullOrWhiteSpace(allowedRoot))
+        {
+            var localAppData = Environment.GetFolderPath(Environment.SpecialFolder.LocalApplicationData);
+            if (string.IsNullOrWhiteSpace(localAppData))
+            {
+                return null;
+            }
+
+            allowedRoot = EnsureTrailingSeparator(Path.Combine(Path.GetFullPath(localAppData), "LanMountainDesktop"));
+        }
+
         var normalizedPluginsDirectory = EnsureTrailingSeparator(Path.GetFullPath(pluginsDirectory));
         if (normalizedPluginsDirectory.StartsWith(allowedRoot, StringComparison.OrdinalIgnoreCase))
         {
diff --git a/LanMountainDesktop.Launcher/Services/StartupAttemptRegistry.cs b/LanMountainDesktop.Launcher/Services/StartupAttemptRegistry.cs
index 8037cd4..a6d3476 100644
--- a/LanMountainDesktop.Launcher/Services/StartupAttemptRegistry.cs
+++ b/LanMountainDesktop.Launcher/Services/StartupAttemptRegistry.cs
@@ -20,15 +20,29 @@ internal sealed class StartupAttemptRegistry
     private string? _ownedAttemptId;
 
     public StartupAttemptRegistry()
-        : this(Path.Combine(
-            Environment.GetFolderPath(Environment.SpecialFolder.LocalApplicationData),
-            "LanMountainDesktop",
-            ".launcher",
-            "state",
-            "startup-attempt.json"))
+        : this(ResolveDefaultStatePath())
     {
     }
 
+    private static string ResolveDefaultStatePath()
+    {
+        try
+        {
+            var appRoot = Commands.ResolveAppRoot(CommandContext.FromArgs([]));
+            var resolver = new DataLocationResolver(appRoot);
+            return Path.Combine(resolver.ResolveDataRoot(), ".launcher", "state", "startup-attempt.json");
+        }
+        catch
+        {
+            return Path.Combine(
+                Environment.GetFolderPath(Environment.SpecialFolder.LocalApplicationData),
+                "LanMountainDesktop",
+                ".launcher",
+                "state",
+                "startup-attempt.json");
+        }
+    }
+
     internal StartupAttemptRegistry(string statePath)
     {
         _statePath = statePath;
diff --git a/LanMountainDesktop.Launcher/Views/DataLocationPromptWindow.axaml b/LanMountainDesktop.Launcher/Views/DataLocationPromptWindow.axaml
new file mode 100644
index 0000000..386cba2
--- /dev/null
+++ b/LanMountainDesktop.Launcher/Views/DataLocationPromptWindow.axaml
@@ -0,0 +1,153 @@
+<Window xmlns="https://github.com/avaloniaui"
+        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+        xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
+        xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
+        xmlns:views="clr-namespace:LanMountainDesktop.Launcher.Views"
+        xmlns:ui="using:FluentAvalonia.UI.Controls"
+        mc:Ignorable="d"
+        d:DesignWidth="520"
+        d:DesignHeight="480"
+        x:Class="LanMountainDesktop.Launcher.Views.DataLocationPromptWindow"
+        x:DataType="views:DataLocationPromptWindow"
+        Title="选择数据保存位置"
+        Width="520"
+        Height="480"
+        CanResize="False"
+        WindowStartupLocation="CenterScreen"
+        Background="{DynamicResource SolidBackgroundFillColorBaseBrush}"
+        TransparencyLevelHint="None"
+        Icon="/Assets/logo.ico">
+  <Grid x:Name="ContentGrid"
+        Opacity="0">
+    <Grid.RenderTransform>
+      <TranslateTransform Y="24" />
+    </Grid.RenderTransform>
+    <Grid Margin="36" RowDefinitions="Auto,*,Auto">
+      <StackPanel Grid.Row="0" Spacing="8" Margin="0,0,0,20">
+        <TextBlock Text="选择数据保存位置"
+                   FontSize="22"
+                   FontWeight="SemiBold"
+                   Foreground="{DynamicResource TextFillColorPrimaryBrush}" />
+        <TextBlock Text="决定将应用数据保存在哪里，可随时在设置中更改"
+                   FontSize="13"
+                   Foreground="{DynamicResource TextFillColorSecondaryBrush}" />
+      </StackPanel>
+
+      <StackPanel Grid.Row="1" Spacing="12">
+        <Border x:Name="AdminWarningBanner"
+                Background="{DynamicResource SystemFillColorCriticalBackgroundBrush}"
+                CornerRadius="{DynamicResource DesignCornerRadiusMd}"
+                Padding="12,10"
+                IsVisible="False">
+          <StackPanel Spacing="4">
+            <StackPanel Orientation="Horizontal" Spacing="6">
+              <ui:SymbolIcon Symbol="Important"
+                             FontSize="16"
+                             Foreground="{DynamicResource SystemFillColorCriticalBrush}" />
+              <TextBlock Text="无法保存到应用目录"
+                         FontWeight="SemiBold"
+                         FontSize="13"
+                         Foreground="{DynamicResource SystemFillColorCriticalBrush}" />
+            </StackPanel>
+            <TextBlock Text="当前安装目录需要管理员权限才能写入，数据将自动保存到系统用户目录。"
+                       FontSize="12"
+                       TextWrapping="Wrap"
+                       Foreground="{DynamicResource SystemFillColorCriticalBrush}" />
+          </StackPanel>
+        </Border>
+
+        <Border x:Name="SystemOptionBorder"
+                Background="{DynamicResource CardBackgroundFillColorDefaultBrush}"
+                CornerRadius="{DynamicResource DesignCornerRadiusMd}"
+                BorderThickness="2"
+                BorderBrush="{DynamicResource AccentFillColorDefaultBrush}"
+                Padding="16,14">
+          <Grid ColumnDefinitions="Auto,*">
+            <RadioButton x:Name="SystemRadio"
+                         Grid.Column="0"
+                         VerticalAlignment="Top"
+                         Margin="0,2,12,0"
+                         GroupName="DataLocation"
+                         IsChecked="True" />
+            <StackPanel Grid.Column="1" Spacing="4">
+              <TextBlock Text="保存在系统用户目录（推荐）"
+                         FontSize="14"
+                         FontWeight="SemiBold"
+                         Foreground="{DynamicResource TextFillColorPrimaryBrush}" />
+              <TextBlock Text="数据与当前 Windows 用户绑定，重装应用或更新后数据不会丢失"
+                         FontSize="12"
+                         TextWrapping="Wrap"
+                         Foreground="{DynamicResource TextFillColorSecondaryBrush}" />
+              <TextBlock x:Name="SystemPathText"
+                         FontSize="11"
+                         TextWrapping="Wrap"
+                         Foreground="{DynamicResource TextFillColorTertiaryBrush}"
+                         Margin="0,4,0,0" />
+            </StackPanel>
+          </Grid>
+        </Border>
+
+        <Border x:Name="PortableOptionBorder"
+                Background="{DynamicResource CardBackgroundFillColorDefaultBrush}"
+                CornerRadius="{DynamicResource DesignCornerRadiusMd}"
+                BorderThickness="1"
+                BorderBrush="{DynamicResource CardStrokeColorDefaultBrush}"
+                Padding="16,14">
+          <Grid ColumnDefinitions="Auto,*">
+            <RadioButton x:Name="PortableRadio"
+                         Grid.Column="0"
+                         VerticalAlignment="Top"
+                         Margin="0,2,12,0"
+                         GroupName="DataLocation"
+                         IsEnabled="False" />
+            <StackPanel Grid.Column="1" Spacing="4">
+              <TextBlock Text="保存在应用安装目录"
+                         FontSize="14"
+                         FontWeight="SemiBold"
+                         Foreground="{DynamicResource TextFillColorPrimaryBrush}" />
+              <TextBlock Text="便于携带，可随应用文件夹整体移动到其他电脑"
+                         FontSize="12"
+                         TextWrapping="Wrap"
+                         Foreground="{DynamicResource TextFillColorSecondaryBrush}" />
+              <TextBlock x:Name="PortablePathText"
+                         FontSize="11"
+                         TextWrapping="Wrap"
+                         Foreground="{DynamicResource TextFillColorTertiaryBrush}"
+                         Margin="0,4,0,0" />
+            </StackPanel>
+          </Grid>
+        </Border>
+
+        <Border x:Name="MigrationInfoBorder"
+                Background="{DynamicResource SystemFillColorSuccessBackgroundBrush}"
+                CornerRadius="{DynamicResource DesignCornerRadiusMd}"
+                Padding="12,10"
+                IsVisible="False">
+          <StackPanel Orientation="Horizontal" Spacing="6">
+            <ui:SymbolIcon Symbol="Message"
+                           FontSize="16"
+                           Foreground="{DynamicResource SystemFillColorSuccessBrush}" />
+            <TextBlock x:Name="MigrationInfoText"
+                       FontSize="12"
+                       TextWrapping="Wrap"
+                       Foreground="{DynamicResource SystemFillColorSuccessBrush}" />
+          </StackPanel>
+        </Border>
+      </StackPanel>
+
+      <StackPanel Grid.Row="2"
+                  Orientation="Horizontal"
+                  HorizontalAlignment="Right"
+                  Spacing="10"
+                  Margin="0,20,0,0">
+        <Button x:Name="CancelButton"
+                Content="取消"
+                Theme="{DynamicResource ButtonTheme}"
+                IsVisible="False" />
+        <Button x:Name="ConfirmButton"
+                Content="确认"
+                Theme="{DynamicResource AccentButtonTheme}" />
+      </StackPanel>
+    </Grid>
+  </Grid>
+</Window>
diff --git a/LanMountainDesktop.Launcher/Views/DataLocationPromptWindow.axaml.cs b/LanMountainDesktop.Launcher/Views/DataLocationPromptWindow.axaml.cs
new file mode 100644
index 0000000..d2cdf2a
--- /dev/null
+++ b/LanMountainDesktop.Launcher/Views/DataLocationPromptWindow.axaml.cs
@@ -0,0 +1,307 @@
+using Avalonia;
+using Avalonia.Animation;
+using Avalonia.Animation.Easings;
+using Avalonia.Controls;
+using Avalonia.Interactivity;
+using Avalonia.Markup.Xaml;
+using Avalonia.Media;
+using Avalonia.Styling;
+using LanMountainDesktop.Launcher.Models;
+using LanMountainDesktop.Launcher.Services;
+
+namespace LanMountainDesktop.Launcher.Views;
+
+internal partial class DataLocationPromptWindow : Window
+{
+    private readonly TaskCompletionSource<DataLocationPromptResult?> _completionSource = new();
+    private readonly DataLocationResolver _resolver;
+    private bool _isTransitioning;
+
+    public DataLocationPromptWindow()
+    {
+        AvaloniaXamlLoader.Load(this);
+        Loaded += OnWindowLoaded;
+        Opened += OnWindowOpened;
+        _resolver = new DataLocationResolver(AppContext.BaseDirectory);
+    }
+
+    internal DataLocationPromptWindow(DataLocationResolver resolver)
+    {
+        AvaloniaXamlLoader.Load(this);
+        Loaded += OnWindowLoaded;
+        Opened += OnWindowOpened;
+        _resolver = resolver;
+    }
+
+    private void OnWindowLoaded(object? sender, RoutedEventArgs e)
+    {
+        BindControls();
+        UpdateUiState();
+    }
+
+    private void BindControls()
+    {
+        var systemRadio = this.FindControl<RadioButton>("SystemRadio");
+        var portableRadio = this.FindControl<RadioButton>("PortableRadio");
+        var confirmButton = this.FindControl<Button>("ConfirmButton");
+        var cancelButton = this.FindControl<Button>("CancelButton");
+
+        if (systemRadio is not null)
+        {
+            systemRadio.Checked += OnSelectionChanged;
+            systemRadio.Unchecked += OnSelectionChanged;
+        }
+
+        if (portableRadio is not null)
+        {
+            portableRadio.Checked += OnSelectionChanged;
+            portableRadio.Unchecked += OnSelectionChanged;
+        }
+
+        if (confirmButton is not null)
+        {
+            confirmButton.Click += OnConfirmClick;
+        }
+
+        if (cancelButton is not null)
+        {
+            cancelButton.Click += OnCancelClick;
+        }
+    }
+
+    private void UpdateUiState()
+    {
+        var systemPathText = this.FindControl<TextBlock>("SystemPathText");
+        var portablePathText = this.FindControl<TextBlock>("PortablePathText");
+        var adminWarningBanner = this.FindControl<Border>("AdminWarningBanner");
+        var portableRadio = this.FindControl<RadioButton>("PortableRadio");
+        var migrationInfoBorder = this.FindControl<Border>("MigrationInfoBorder");
+        var migrationInfoText = this.FindControl<TextBlock>("MigrationInfoText");
+
+        if (systemPathText is not null)
+        {
+            systemPathText.Text = _resolver.DefaultSystemDataPath;
+        }
+
+        if (portablePathText is not null)
+        {
+            portablePathText.Text = _resolver.DefaultPortableDataPath;
+        }
+
+        var portableAllowed = _resolver.IsPortableModeAllowed();
+
+        if (adminWarningBanner is not null)
+        {
+            adminWarningBanner.IsVisible = !portableAllowed;
+        }
+
+        if (portableRadio is not null)
+        {
+            portableRadio.IsEnabled = portableAllowed;
+        }
+
+        var hasExistingData = _resolver.HasExistingSystemData();
+        if (migrationInfoBorder is not null)
+        {
+            migrationInfoBorder.IsVisible = hasExistingData;
+        }
+
+        if (migrationInfoText is not null && hasExistingData)
+        {
+            migrationInfoText.Text = "检测到系统用户目录已有应用数据。如果选择保存在应用安装目录，将自动迁移现有数据。";
+        }
+    }
+
+    private void OnSelectionChanged(object? sender, RoutedEventArgs e)
+    {
+        var systemRadio = this.FindControl<RadioButton>("SystemRadio");
+        var portableRadio = this.FindControl<RadioButton>("PortableRadio");
+        var systemBorder = this.FindControl<Border>("SystemOptionBorder");
+        var portableBorder = this.FindControl<Border>("PortableOptionBorder");
+
+        var isSystem = systemRadio?.IsChecked == true;
+        var isPortable = portableRadio?.IsChecked == true;
+
+        if (systemBorder is not null)
+        {
+            systemBorder.BorderBrush = isSystem
+                ? Application.Current?.FindResource("AccentFillColorDefaultBrush") as IBrush
+                : Application.Current?.FindResource("CardStrokeColorDefaultBrush") as IBrush;
+            systemBorder.BorderThickness = isSystem ? new Thickness(2) : new Thickness(1);
+        }
+
+        if (portableBorder is not null)
+        {
+            portableBorder.BorderBrush = isPortable
+                ? Application.Current?.FindResource("AccentFillColorDefaultBrush") as IBrush
+                : Application.Current?.FindResource("CardStrokeColorDefaultBrush") as IBrush;
+            portableBorder.BorderThickness = isPortable ? new Thickness(2) : new Thickness(1);
+        }
+    }
+
+    private async void OnConfirmClick(object? sender, RoutedEventArgs e)
+    {
+        if (_isTransitioning)
+        {
+            return;
+        }
+
+        _isTransitioning = true;
+
+        var portableRadio = this.FindControl<RadioButton>("PortableRadio");
+        var selectedMode = portableRadio?.IsChecked == true
+            ? DataLocationMode.Portable
+            : DataLocationMode.System;
+
+        var migrateExistingData = selectedMode == DataLocationMode.Portable && _resolver.HasExistingSystemData();
+
+        try
+        {
+            await PlayExitAnimationAsync();
+            _completionSource.TrySetResult(new DataLocationPromptResult
+            {
+                SelectedMode = selectedMode,
+                MigrateExistingData = migrateExistingData
+            });
+        }
+        catch (Exception ex)
+        {
+            Logger.Warn($"Error during data location prompt exit animation: {ex.Message}");
+            _completionSource.TrySetResult(new DataLocationPromptResult
+            {
+                SelectedMode = selectedMode,
+                MigrateExistingData = migrateExistingData
+            });
+        }
+    }
+
+    private async void OnCancelClick(object? sender, RoutedEventArgs e)
+    {
+        if (_isTransitioning)
+        {
+            return;
+        }
+
+        _isTransitioning = true;
+
+        try
+        {
+            await PlayExitAnimationAsync();
+            _completionSource.TrySetResult(null);
+        }
+        catch (Exception ex)
+        {
+            Logger.Warn($"Error during data location prompt cancel: {ex.Message}");
+            _completionSource.TrySetResult(null);
+        }
+    }
+
+    private async void OnWindowOpened(object? sender, EventArgs e)
+    {
+        await PlayEntranceAnimationAsync();
+    }
+
+    private async Task PlayEntranceAnimationAsync()
+    {
+        try
+        {
+            var contentGrid = this.FindControl<Grid>("ContentGrid");
+            if (contentGrid is null)
+            {
+                return;
+            }
+
+            var translateTransform = contentGrid.RenderTransform as TranslateTransform ?? new TranslateTransform();
+            contentGrid.RenderTransform = translateTransform;
+
+            contentGrid.Opacity = 0;
+            translateTransform.Y = 24;
+
+            var fadeInAnimation = new Animation
+            {
+                Duration = TimeSpan.FromMilliseconds(500),
+                Easing = new CubicEaseOut(),
+                Children =
+                {
+                    new KeyFrame
+                    {
+                        Setters = { new Setter(OpacityProperty, 0.0) },
+                        KeyTime = TimeSpan.FromMilliseconds(0)
+                    },
+                    new KeyFrame
+                    {
+                        Setters = { new Setter(OpacityProperty, 1.0) },
+                        KeyTime = TimeSpan.FromMilliseconds(500)
+                    }
+                }
+            };
+
+            var slideUpAnimation = new Animation
+            {
+                Duration = TimeSpan.FromMilliseconds(500),
+                Easing = new CubicEaseOut(),
+                Children =
+                {
+                    new KeyFrame
+                    {
+                        Setters = { new Setter(TranslateTransform.YProperty, 24.0) },
+                        KeyTime = TimeSpan.FromMilliseconds(0)
+                    },
+                    new KeyFrame
+                    {
+                        Setters = { new Setter(TranslateTransform.YProperty, 0.0) },
+                        KeyTime = TimeSpan.FromMilliseconds(500)
+                    }
+                }
+            };
+
+            await Task.WhenAll(
+                fadeInAnimation.RunAsync(contentGrid),
+                slideUpAnimation.RunAsync(translateTransform));
+        }
+        catch (Exception ex)
+        {
+            Logger.Warn($"Error playing data location prompt entrance animation: {ex.Message}");
+        }
+    }
+
+    private async Task PlayExitAnimationAsync()
+    {
+        try
+        {
+            var contentGrid = this.FindControl<Grid>("ContentGrid");
+            if (contentGrid is null)
+            {
+                await Task.Delay(150);
+                return;
+            }
+
+            var fadeOutAnimation = new Animation
+            {
+                Duration = TimeSpan.FromMilliseconds(200),
+                Easing = new CubicEaseIn(),
+                Children =
+                {
+                    new KeyFrame
+                    {
+                        Setters = { new Setter(OpacityProperty, 1.0) },
+                        KeyTime = TimeSpan.FromMilliseconds(0)
+                    },
+                    new KeyFrame
+                    {
+                        Setters = { new Setter(OpacityProperty, 0.0) },
+                        KeyTime = TimeSpan.FromMilliseconds(200)
+                    }
+                }
+            };
+
+            await fadeOutAnimation.RunAsync(contentGrid);
+        }
+        catch (Exception ex)
+        {
+            Logger.Warn($"Error playing data location prompt exit animation: {ex.Message}");
+        }
+    }
+
+    internal Task<DataLocationPromptResult?> WaitForChoiceAsync() => _completionSource.Task;
+}
diff --git a/LanMountainDesktop/Program.cs b/LanMountainDesktop/Program.cs
index 66b5be6..9e78bde 100644
--- a/LanMountainDesktop/Program.cs
+++ b/LanMountainDesktop/Program.cs
@@ -22,6 +22,7 @@ public sealed class Program
     public static void Main(string[] args)
     {
         AppLogger.Initialize();
+        AppDataPathProvider.Initialize(args);
         DevPluginOptions.Parse(args);
         RegisterGlobalExceptionLogging();
         var restartParentProcessId = LauncherRuntimeMetadata.GetRestartParentProcessId(args);
diff --git a/LanMountainDesktop/Services/AppDataPathProvider.cs b/LanMountainDesktop/Services/AppDataPathProvider.cs
new file mode 100644
index 0000000..55d6f5a
--- /dev/null
+++ b/LanMountainDesktop/Services/AppDataPathProvider.cs
@@ -0,0 +1,66 @@
+namespace LanMountainDesktop.Services;
+
+public static class AppDataPathProvider
+{
+    private static string? _overriddenDataRoot;
+
+    public static void Initialize(string[] args)
+    {
+        var dataRoot = ResolveDataRootFromArgs(args);
+        if (!string.IsNullOrWhiteSpace(dataRoot))
+        {
+            _overriddenDataRoot = Path.GetFullPath(dataRoot);
+            AppLogger.Info("AppDataPath", $"Data root overridden by launcher: '{_overriddenDataRoot}'.");
+        }
+        else
+        {
+            var envDataRoot = Environment.GetEnvironmentVariable("LMD_DATA_ROOT");
+            if (!string.IsNullOrWhiteSpace(envDataRoot))
+            {
+                _overriddenDataRoot = Path.GetFullPath(envDataRoot);
+                AppLogger.Info("AppDataPath", $"Data root overridden by environment variable: '{_overriddenDataRoot}'.");
+            }
+        }
+    }
+
+    public static string GetDataRoot()
+    {
+        if (!string.IsNullOrWhiteSpace(_overriddenDataRoot))
+        {
+            return _overriddenDataRoot;
+        }
+
+        return Path.Combine(
+            Environment.GetFolderPath(Environment.SpecialFolder.LocalApplicationData),
+            "LanMountainDesktop");
+    }
+
+    public static string GetSettingsDirectory()
+    {
+        return GetDataRoot();
+    }
+
+    public static string GetPluginMarketDirectory()
+    {
+        return Path.Combine(GetDataRoot(), "PluginMarket");
+    }
+
+    public static string GetWallpapersDirectory()
+    {
+        return Path.Combine(GetDataRoot(), "Wallpapers");
+    }
+
+    private static string? ResolveDataRootFromArgs(string[] args)
+    {
+        const string prefix = "--data-root=";
+        foreach (var arg in args)
+        {
+            if (arg.StartsWith(prefix, StringComparison.OrdinalIgnoreCase))
+            {
+                return arg[prefix.Length..];
+            }
+        }
+
+        return null;
+    }
+}
diff --git a/LanMountainDesktop/Services/AppDatabaseService.cs b/LanMountainDesktop/Services/AppDatabaseService.cs
index d68ebb2..6f79f49 100644
--- a/LanMountainDesktop/Services/AppDatabaseService.cs
+++ b/LanMountainDesktop/Services/AppDatabaseService.cs
@@ -24,8 +24,7 @@ public sealed class AppDatabaseService
 
     public AppDatabaseService()
     {
-        var appData = Environment.GetFolderPath(Environment.SpecialFolder.LocalApplicationData);
-        var dataDirectory = Path.Combine(appData, "LanMountainDesktop");
+        var dataDirectory = AppDataPathProvider.GetDataRoot();
         _databasePath = Path.Combine(dataDirectory, "app.db");
     }
 
diff --git a/LanMountainDesktop/Services/AppSettingsService.cs b/LanMountainDesktop/Services/AppSettingsService.cs
index 285740c..d1b48b9 100644
--- a/LanMountainDesktop/Services/AppSettingsService.cs
+++ b/LanMountainDesktop/Services/AppSettingsService.cs
@@ -27,8 +27,7 @@ public sealed class AppSettingsService
 
     public AppSettingsService()
     {
-        var appData = Environment.GetFolderPath(Environment.SpecialFolder.LocalApplicationData);
-        var settingsDirectory = Path.Combine(appData, "LanMountainDesktop");
+        var settingsDirectory = AppDataPathProvider.GetSettingsDirectory();
         _settingsPath = Path.Combine(settingsDirectory, "settings.json");
     }
 
diff --git a/LanMountainDesktop/Services/LauncherSettingsService.cs b/LanMountainDesktop/Services/LauncherSettingsService.cs
index 12b39b6..796576f 100644
--- a/LanMountainDesktop/Services/LauncherSettingsService.cs
+++ b/LanMountainDesktop/Services/LauncherSettingsService.cs
@@ -30,8 +30,7 @@ public sealed class LauncherSettingsService
 
     public LauncherSettingsService()
     {
-        var appData = Environment.GetFolderPath(Environment.SpecialFolder.LocalApplicationData);
-        var settingsDirectory = Path.Combine(appData, "LanMountainDesktop");
+        var settingsDirectory = AppDataPathProvider.GetSettingsDirectory();
         _settingsPath = Path.Combine(settingsDirectory, "launcher-settings.json");
         _legacyAppSettingsPath = Path.Combine(settingsDirectory, "settings.json");
     }
diff --git a/LanMountainDesktop/Services/Settings/ComponentDomainStorage.cs b/LanMountainDesktop/Services/Settings/ComponentDomainStorage.cs
index 13b608a..097955f 100644
--- a/LanMountainDesktop/Services/Settings/ComponentDomainStorage.cs
+++ b/LanMountainDesktop/Services/Settings/ComponentDomainStorage.cs
@@ -76,9 +76,7 @@ internal sealed class SqliteComponentDomainStorage :
     public SqliteComponentDomainStorage(string? settingsRoot = null)
     {
         _settingsRoot = string.IsNullOrWhiteSpace(settingsRoot)
-            ? Path.Combine(
-                Environment.GetFolderPath(Environment.SpecialFolder.LocalApplicationData),
-                "LanMountainDesktop")
+            ? AppDataPathProvider.GetDataRoot()
             : settingsRoot.Trim();
         _dbPath = Path.Combine(_settingsRoot, "component-state.db");
         _layoutJsonPath = Path.Combine(_settingsRoot, "desktop-layout-settings.json");
diff --git a/LanMountainDesktop/Services/Settings/SettingsDomainServices.cs b/LanMountainDesktop/Services/Settings/SettingsDomainServices.cs
index 201759a..6520cdd 100644
--- a/LanMountainDesktop/Services/Settings/SettingsDomainServices.cs
+++ b/LanMountainDesktop/Services/Settings/SettingsDomainServices.cs
@@ -167,10 +167,7 @@ internal sealed class WallpaperMediaService : IWallpaperMediaService
 
     public WallpaperMediaService()
     {
-        var appDataRoot = Path.Combine(
-            Environment.GetFolderPath(Environment.SpecialFolder.LocalApplicationData),
-            "LanMountainDesktop");
-        _wallpapersDirectory = Path.Combine(appDataRoot, "Wallpapers");
+        _wallpapersDirectory = AppDataPathProvider.GetWallpapersDirectory();
     }
 
     public WallpaperMediaType DetectMediaType(string? path)
@@ -1026,10 +1023,7 @@ internal sealed class PluginCatalogSettingsService : IPluginCatalogSettingsServi
     {
         _pluginRuntimeService = pluginRuntimeService;
 
-        var dataRoot = Path.Combine(
-            Environment.GetFolderPath(Environment.SpecialFolder.LocalApplicationData),
-            "LanMountainDesktop",
-            "PluginMarket");
+        var dataRoot = AppDataPathProvider.GetPluginMarketDirectory();
         var cacheService = new AirAppMarketCacheService(dataRoot);
         _indexService = new AirAppMarketIndexService(cacheService);
         if (_pluginRuntimeService is not null)
@@ -1049,10 +1043,7 @@ internal sealed class PluginCatalogSettingsService : IPluginCatalogSettingsServi
             return;
         }
 
-        var dataRoot = Path.Combine(
-            Environment.GetFolderPath(Environment.SpecialFolder.LocalApplicationData),
-            "LanMountainDesktop",
-            "PluginMarket");
+        var dataRoot = AppDataPathProvider.GetPluginMarketDirectory();
         _installService = new AirAppMarketInstallService(_pluginRuntimeService, dataRoot);
     }
 
diff --git a/LanMountainDesktop/Services/Settings/SettingsService.cs b/LanMountainDesktop/Services/Settings/SettingsService.cs
index 9f091c7..df41063 100644
--- a/LanMountainDesktop/Services/Settings/SettingsService.cs
+++ b/LanMountainDesktop/Services/Settings/SettingsService.cs
@@ -26,9 +26,7 @@ internal sealed class SettingsService : ISettingsService
 
     public SettingsService()
     {
-        var root = Path.Combine(
-            Environment.GetFolderPath(Environment.SpecialFolder.LocalApplicationData),
-            "LanMountainDesktop");
+        var root = AppDataPathProvider.GetDataRoot();
         _pluginSettingsPath = Path.Combine(root, "plugin-settings.json");
     }