changed.调整了启动逻辑，优化了更新页面。

LanMountainDesktop.Launcher/Services/DeploymentLocator.cs

@@ -1,5 +1,6 @@
 using System.Globalization;
 using System.Text.Json;
+using LanMountainDesktop.Launcher.Models;
 using LanMountainDesktop.Shared.Contracts.Launcher;
 
 namespace LanMountainDesktop.Launcher.Services;
@@ -17,44 +18,65 @@ internal sealed class DeploymentLocator
 
     public string? FindCurrentDeploymentDirectory()
     {
-        var candidates = Directory.Exists(_appRoot)
-            ? Directory.GetDirectories(_appRoot, "app-*", SearchOption.TopDirectoryOnly)
-            : [];
+        Console.WriteLine("[DeploymentLocator] Searching for deployment directories (ClassIsland style)...");
 
-        // 过滤掉无效的部署目录
-        var validCandidates = candidates
-            .Where(path => 
-                !File.Exists(Path.Combine(path, ".destroy")) &&    // 排除待删除
-                !File.Exists(Path.Combine(path, ".partial")))      // 排除未完成
-            .ToList();
-
-        // 优先选择带 .current 标记的版本
-        var withMarkers = validCandidates
-            .Where(path => File.Exists(Path.Combine(path, ".current")))
-            .Select(path => new
-            {
-                Path = path,
-                Version = ParseVersionFromDirectory(path)
-            })
-            .OrderByDescending(item => item.Version)
-            .ToList();
-
-        if (withMarkers.Count > 0)
+        if (!Directory.Exists(_appRoot))
         {
-            return withMarkers[0].Path;
+            Console.WriteLine("[DeploymentLocator] App root directory does not exist");
+            return null;
         }
 
-        // 如果没有 .current 标记,选择最新版本
-        var byVersion = validCandidates
-            .Select(path => new
-            {
-                Path = path,
-                Version = ParseVersionFromDirectory(path)
-            })
-            .OrderByDescending(item => item.Version)
-            .ToList();
+        var executable = OperatingSystem.IsWindows() ? "LanMountainDesktop.exe" : "LanMountainDesktop";
 
-        return byVersion.Count > 0 ? byVersion[0].Path : null;
+        try
+        {
+            var candidates = Directory.GetDirectories(_appRoot, "app-*", SearchOption.TopDirectoryOnly);
+            Console.WriteLine($"[DeploymentLocator] Found {candidates.Length} app-* directories");
+
+            // ClassIsland 风格的查询：先筛选，后排序
+            var validInstallations = candidates
+                .Where(path =>
+                {
+                    var hasDestroy = File.Exists(Path.Combine(path, ".destroy"));
+                    var hasPartial = File.Exists(Path.Combine(path, ".partial"));
+                    var hasExe = File.Exists(Path.Combine(path, executable));
+                    var hasCurrent = File.Exists(Path.Combine(path, ".current"));
+                    var version = ParseVersionFromDirectory(path);
+
+                    Console.WriteLine($"[DeploymentLocator] Candidate: {Path.GetFileName(path)} | " +
+                        $"Version={version} | " +
+                        $"Current={hasCurrent} | " +
+                        $"Destroy={hasDestroy} | " +
+                        $"Partial={hasPartial} | " +
+                        $"HasExe={hasExe}");
+
+                    return !hasDestroy && !hasPartial && hasExe;
+                })
+                .Select(path => new
+                {
+                    Path = path,
+                    Version = ParseVersionFromDirectory(path),
+                    HasCurrentMarker = File.Exists(Path.Combine(path, ".current"))
+                })
+                .OrderBy(x => x.HasCurrentMarker ? 0 : 1)  // .current 标记的排前面
+                .ThenByDescending(x => x.Version)  // 然后按版本号降序
+                .ToList();
+
+            if (validInstallations.Count == 0)
+            {
+                Console.WriteLine("[DeploymentLocator] No valid deployment directories found");
+                return null;
+            }
+
+            var best = validInstallations[0];
+            Console.WriteLine($"[DeploymentLocator] Selected: {Path.GetFileName(best.Path)} (current={best.HasCurrentMarker}, version={best.Version})");
+            return best.Path;
+        }
+        catch (Exception ex)
+        {
+            Console.Error.WriteLine($"[DeploymentLocator] Error searching for deployments: {ex}");
+            return null;
+        }
     }
 
     public string? ResolveHostExecutablePath()
@@ -233,35 +255,159 @@ internal sealed class DeploymentLocator
         }
     }
 
-    public void CleanupDestroyedDeployments()
+    /// <summary>
+    /// 清理旧版本部署，保留最近的N个版本
+    /// </summary>
+    /// <param name="minVersionsToKeep">最少保留版本数，默认3个</param>
+    public void CleanupOldDeployments(int minVersionsToKeep = 3)
     {
         try
         {
-            var candidates = Directory.Exists(_appRoot)
-                ? Directory.GetDirectories(_appRoot, "app-*", SearchOption.TopDirectoryOnly)
-                : [];
+            Console.WriteLine($"[DeploymentLocator] Starting cleanup with retention policy: keep at least {minVersionsToKeep} versions");
 
-            var destroyedDirs = candidates
-                .Where(path => File.Exists(Path.Combine(path, ".destroy")));
+            if (!Directory.Exists(_appRoot))
+            {
+                return;
+            }
 
-            foreach (var dir in destroyedDirs)
+            var candidates = Directory.GetDirectories(_appRoot, "app-*", SearchOption.TopDirectoryOnly);
+
+            // 过滤掉无效部署目录（排除partial），按版本排序
+            var validDeployments = candidates
+                .Where(path => !File.Exists(Path.Combine(path, ".partial")))
+                .Select(path => new
+                {
+                    Path = path,
+                    Version = ParseVersionFromDirectory(path),
+                    IsDestroyed = File.Exists(Path.Combine(path, ".destroy")),
+                    IsCurrent = File.Exists(Path.Combine(path, ".current"))
+                })
+                .OrderByDescending(item => item.Version)
+                .ToList();
+
+            Console.WriteLine($"[DeploymentLocator] Found {validDeployments.Count} valid deployments");
+
+            // 确定要保留的版本
+            var versionsToKeep = new HashSet<string>();
+
+            // 1. 总是保留当前版本
+            var currentVersion = validDeployments.FirstOrDefault(d => d.IsCurrent);
+            if (currentVersion != null)
+            {
+                versionsToKeep.Add(currentVersion.Path);
+                Console.WriteLine($"[DeploymentLocator] Keep current version: {currentVersion.Path}");
+            }
+
+            // 2. 保留最近的N个有效版本（不包括已标记destroy的）
+            var activeVersions = validDeployments
+                .Where(d => !d.IsDestroyed)
+                .Take(minVersionsToKeep)
+                .ToList();
+
+            foreach (var ver in activeVersions)
+            {
+                versionsToKeep.Add(ver.Path);
+                Console.WriteLine($"[DeploymentLocator] Keep recent version: {ver.Path}");
+            }
+
+            // 3. 保留有快照的版本（用于回滚）
+            var snapshotDir = Path.Combine(_appRoot, ".launcher", "snapshots");
+            if (Directory.Exists(snapshotDir))
             {
                 try
                 {
-                    Directory.Delete(dir, recursive: true);
+                    var snapshotFiles = Directory.GetFiles(snapshotDir, "*.json", SearchOption.TopDirectoryOnly);
+                    foreach (var snapshotFile in snapshotFiles)
+                    {
+                        try
+                        {
+                            var json = File.ReadAllText(snapshotFile);
+                            var snapshot = System.Text.Json.JsonSerializer.Deserialize<SnapshotMetadata>(json);
+                            if (snapshot != null && !string.IsNullOrEmpty(snapshot.SourceDirectory))
+                            {
+                                if (Directory.Exists(snapshot.SourceDirectory))
+                                {
+                                    versionsToKeep.Add(snapshot.SourceDirectory);
+                                    Console.WriteLine($"[DeploymentLocator] Keep version for rollback: {snapshot.SourceDirectory}");
+                                }
+                            }
+                        }
+                        catch
+                        {
+                            // 忽略快照解析错误
+                        }
+                    }
+                }
+                catch
+                {
+                    // 忽略快照目录访问错误
+                }
+            }
+
+            // 清理不需要的版本
+            foreach (var deployment in validDeployments)
+            {
+                if (versionsToKeep.Contains(deployment.Path))
+                {
+                    // 保留此版本，如果之前标记了destroy则取消标记
+                    if (deployment.IsDestroyed)
+                    {
+                        try
+                        {
+                            File.Delete(Path.Combine(deployment.Path, ".destroy"));
+                            Console.WriteLine($"[DeploymentLocator] Unmarked for deletion (kept): {deployment.Path}");
+                        }
+                        catch
+                        {
+                            // 忽略取消标记失败
+                        }
+                    }
+                    continue;
+                }
+
+                // 如果还没标记destroy的，先标记
+                if (!deployment.IsDestroyed)
+                {
+                    try
+                    {
+                        File.WriteAllText(Path.Combine(deployment.Path, ".destroy"), string.Empty);
+                        Console.WriteLine($"[DeploymentLocator] Marked for deletion: {deployment.Path}");
+                    }
+                    catch
+                    {
+                        // 忽略标记失败
+                    }
+                }
+
+                // 尝试删除
+                try
+                {
+                    Directory.Delete(deployment.Path, recursive: true);
+                    Console.WriteLine($"[DeploymentLocator] Deleted: {deployment.Path}");
                 }
                 catch
                 {
                     // 忽略删除失败(可能文件被占用),下次启动再试
+                    Console.WriteLine($"[DeploymentLocator] Failed to delete (will retry later): {deployment.Path}");
                 }
             }
         }
-        catch
+        catch (Exception ex)
         {
+            Console.Error.WriteLine($"[DeploymentLocator] Cleanup failed: {ex.Message}");
             // 忽略清理失败
         }
     }
 
+    /// <summary>
+    /// 仅清理已标记为.destroy的部署（兼容旧方法）
+    /// </summary>
+    [Obsolete("Use CleanupOldDeployments instead")]
+    public void CleanupDestroyedDeployments()
+    {
+        CleanupOldDeployments(3);
+    }
+
     public static Version ParseVersionFromDirectory(string path)
     {
         var text = ParseVersionTextFromDirectory(path);

LanMountainDesktop.Launcher/Services/FlexibleHostLocator.cs

@@ -4,50 +4,67 @@ using System.Text.Json;
 namespace LanMountainDesktop.Launcher.Services;
 
 /// <summary>
-/// 灵活的主程序定位器
-/// </summary>
-internal sealed class FlexibleHostLocator
-{
-    private readonly HostDiscoveryOptions _options;
-    private readonly string _appRoot;
-
-    public FlexibleHostLocator(string appRoot, HostDiscoveryOptions? options = null)
-    {
-        _appRoot = appRoot;
-        _options = options ?? new HostDiscoveryOptions();
-    }
-
-    /// <summary>
-    /// 解析主程序可执行文件路径
+    /// 灵活的主程序定位器
     /// </summary>
-    public string? ResolveHostExecutablePath()
+    internal sealed class FlexibleHostLocator
     {
-        var executable = GetExecutableName();
-        var searchContext = new SearchContext
-        {
-            ExecutableName = executable,
-            AppRoot = _appRoot,
-            Options = _options
-        };
+        private readonly HostDiscoveryOptions _options;
+        private readonly string _appRoot;
+        private readonly DeploymentLocator _deploymentLocator;
 
-        // ========== 第一阶段：标准路径查找（快速路径）==========
-        
-        // 1. 检查环境变量指定的路径（最高优先级 - 用于调试和特殊场景）
-        var envPath = GetPathFromEnvironment();
-        if (!string.IsNullOrWhiteSpace(envPath))
+        public FlexibleHostLocator(string appRoot, HostDiscoveryOptions? options = null)
         {
-            var validated = ValidateAndReturn(envPath, "environment variable");
-            if (validated != null) return validated;
+            _appRoot = appRoot;
+            _options = options ?? new HostDiscoveryOptions();
+            _deploymentLocator = new DeploymentLocator(appRoot);
         }
 
-        // 2. 搜索部署目录（app-*）- 生产环境标准路径
-        var deploymentPath = SearchDeploymentDirectories(searchContext);
-        if (!string.IsNullOrWhiteSpace(deploymentPath))
+        /// <summary>
+        /// 解析主程序可执行文件路径
+        /// </summary>
+        public string? ResolveHostExecutablePath()
         {
-            return deploymentPath;
-        }
+            var executable = GetExecutableName();
+            var searchContext = new SearchContext
+            {
+                ExecutableName = executable,
+                AppRoot = _appRoot,
+                Options = _options
+            };
 
-        // 3. 检查 Launcher 同级目录（便携模式）
+            // ========== 第一阶段：标准路径查找（快速路径）==========
+            
+            // 1. 检查环境变量指定的路径（最高优先级 - 用于调试和特殊场景）
+            var envPath = GetPathFromEnvironment();
+            if (!string.IsNullOrWhiteSpace(envPath))
+            {
+                var validated = ValidateAndReturn(envPath, "environment variable");
+                if (validated != null) return validated;
+            }
+
+            // 2. 使用 DeploymentLocator（ClassIsland 风格的简洁查询 - 优先）
+            Console.WriteLine("[FlexibleHostLocator] Trying quick path: DeploymentLocator.FindCurrentDeploymentDirectory()");
+            var deploymentDir = _deploymentLocator.FindCurrentDeploymentDirectory();
+            if (!string.IsNullOrWhiteSpace(deploymentDir))
+            {
+                var deploymentExePath = Path.Combine(deploymentDir, executable);
+                if (File.Exists(deploymentExePath))
+                {
+                    Console.WriteLine($"[FlexibleHostLocator] Quick path found: {deploymentExePath}");
+                    return deploymentExePath;
+                }
+                Console.WriteLine($"[FlexibleHostLocator] Quick path found dir but no exe: {deploymentExePath}");
+            }
+
+            // 3. 快速路径失败，尝试旧的 SearchDeploymentDirectories 作为 fallback
+            Console.WriteLine("[FlexibleHostLocator] Quick path failed, falling back to SearchDeploymentDirectories");
+            var deploymentPath = SearchDeploymentDirectories(searchContext);
+            if (!string.IsNullOrWhiteSpace(deploymentPath))
+            {
+                return deploymentPath;
+            }
+
+        // 4. 检查 Launcher 同级目录（便携模式）
         var portablePath = SearchPortableLocation(searchContext);
         if (!string.IsNullOrWhiteSpace(portablePath))
         {
@@ -56,7 +73,7 @@ internal sealed class FlexibleHostLocator
 
         // ========== 第二阶段：灵活查找（标准路径找不到时）==========
         
-        // 4. 检查配置文件中的路径 - 用户自定义配置
+        // 5. 检查配置文件中的路径 - 用户自定义配置
         var configPath = GetPathFromConfigFile();
         if (!string.IsNullOrWhiteSpace(configPath))
         {
@@ -71,7 +88,7 @@ internal sealed class FlexibleHostLocator
             return nearbyPath;
         }
 
-        // 6. 开发模式：检查保存的自定义路径
+        // 7. 开发模式：检查保存的自定义路径
         if (_options.PreferDevModeConfig && Views.ErrorWindow.CheckDevModeEnabled())
         {
             var savedPath = Views.ErrorWindow.GetSavedCustomHostPath();
@@ -82,21 +99,21 @@ internal sealed class FlexibleHostLocator
             }
         }
 
-        // 7. 搜索标准开发路径
+        // 8. 搜索标准开发路径
         var devPath = SearchDevelopmentPaths(searchContext);
         if (!string.IsNullOrWhiteSpace(devPath))
         {
             return devPath;
         }
 
-        // 8. 搜索额外的配置路径
+        // 9. 搜索额外的配置路径
         var additionalPath = SearchAdditionalPaths(searchContext);
         if (!string.IsNullOrWhiteSpace(additionalPath))
         {
             return additionalPath;
         }
 
-        // 9. 递归搜索（如果启用）
+        // 10. 递归搜索（如果启用）
         if (_options.RecursiveSearch)
         {
             var recursivePath = SearchRecursively(searchContext);

LanMountainDesktop.Launcher/Services/LauncherFlowCoordinator.cs

@@ -38,8 +38,8 @@ internal sealed class LauncherFlowCoordinator
     {
         try
         {
-            // 清理待删除的旧版本
-            _deploymentLocator.CleanupDestroyedDeployments();
+            // 清理旧版本，保留至少3个版本
+            _deploymentLocator.CleanupOldDeployments(minVersionsToKeep: 3);
 
             // 使用传入的 Splash 窗口或创建新的
             var splashWindow = existingSplashWindow ?? await Dispatcher.UIThread.InvokeAsync(() =>

LanMountainDesktop.Launcher/Services/Logger.cs

@@ -0,0 +1,138 @@
+using System.Text;
+
+namespace LanMountainDesktop.Launcher.Services;
+
+/// <summary>
+/// 简单的日志记录器 - 同时输出到控制台和文件
+/// </summary>
+internal static class Logger
+{
+    private static readonly object _lock = new();
+    private static string? _logFilePath;
+    private static bool _initialized;
+
+    /// <summary>
+    /// 初始化日志记录器
+    /// </summary>
+    public static void Initialize()
+    {
+        if (_initialized)
+        {
+            return;
+        }
+
+        try
+        {
+            var logDir = GetLogDirectory();
+            if (!string.IsNullOrEmpty(logDir))
+            {
+                Directory.CreateDirectory(logDir);
+                var timestamp = DateTime.Now.ToString("yyyyMMdd_HHmmss");
+                _logFilePath = Path.Combine(logDir, $"launcher_{timestamp}.log");
+                Console.WriteLine($"[Logger] Log file initialized: {_logFilePath}");
+            }
+        }
+        catch (Exception ex)
+        {
+            Console.Error.WriteLine($"[Logger] Failed to initialize log file: {ex.Message}");
+        }
+
+        _initialized = true;
+    }
+
+    /// <summary>
+    /// 获取日志文件路径
+    /// </summary>
+    public static string? GetLogFilePath()
+    {
+        return _logFilePath;
+    }
+
+    /// <summary>
+    /// 获取日志目录
+    /// </summary>
+    private static string? GetLogDirectory()
+    {
+        try
+        {
+            var appData = Environment.GetFolderPath(Environment.SpecialFolder.LocalApplicationData);
+            if (!string.IsNullOrEmpty(appData))
+            {
+                return Path.Combine(appData, "LanMountainDesktop", ".launcher", "logs");
+            }
+        }
+        catch
+        {
+        }
+
+        try
+        {
+            var launcherDir = AppContext.BaseDirectory;
+            return Path.Combine(launcherDir, ".launcher", "logs");
+        }
+        catch
+        {
+        }
+
+        return null;
+    }
+
+    /// <summary>
+    /// 记录信息日志
+    /// </summary>
+    public static void Info(string message)
+    {
+        WriteLog("INFO", message);
+    }
+
+    /// <summary>
+    /// 记录警告日志
+    /// </summary>
+    public static void Warn(string message)
+    {
+        WriteLog("WARN", message);
+    }
+
+    /// <summary>
+    /// 记录错误日志
+    /// </summary>
+    public static void Error(string message)
+    {
+        WriteLog("ERROR", message);
+    }
+
+    /// <summary>
+    /// 记录错误日志（带异常）
+    /// </summary>
+    public static void Error(string message, Exception exception)
+    {
+        WriteLog("ERROR", $"{message}\n{exception}");
+    }
+
+    /// <summary>
+    /// 写入日志
+    /// </summary>
+    private static void WriteLog(string level, string message)
+    {
+        var timestamp = DateTime.Now.ToString("yyyy-MM-dd HH:mm:ss.fff");
+        var logLine = $"[{timestamp}] [{level}] {message}";
+
+        Console.WriteLine(logLine);
+
+        if (string.IsNullOrEmpty(_logFilePath))
+        {
+            return;
+        }
+
+        try
+        {
+            lock (_lock)
+            {
+                File.AppendAllText(_logFilePath, logLine + Environment.NewLine, Encoding.UTF8);
+            }
+        }
+        catch
+        {
+        }
+    }
+}

LanMountainDesktop.Launcher/Services/OobeStateService.cs

@@ -6,29 +6,99 @@ internal sealed class OobeStateService
 
     public OobeStateService(string appRoot)
     {
-        // 将 OOBE 状态文件存储在用户可写的 LocalApplicationData 目录中，
-        // 而不是安装目录（Program Files 下普通用户没有写入权限）。
-        var appDataDir = Path.Combine(
-            Environment.GetFolderPath(Environment.SpecialFolder.LocalApplicationData),
-            "LanMountainDesktop");
-        var stateDir = Path.Combine(appDataDir, ".launcher", "state");
-        Directory.CreateDirectory(stateDir);
+        // 优先使用 LocalApplicationData（用户目录，普通用户一定有权限）
+        string? stateDir = null;
+        Exception? lastException = null;
+
+        // 策略1: LocalApplicationData（首选，用户目录，普通用户一定有写权限）
+        try
+        {
+            var appDataDir = Path.Combine(
+                Environment.GetFolderPath(Environment.SpecialFolder.LocalApplicationData),
+                "LanMountainDesktop");
+            stateDir = Path.Combine(appDataDir, ".launcher", "state");
+            Directory.CreateDirectory(stateDir);
+            Console.WriteLine($"[OobeStateService] Using LocalApplicationData: {stateDir}");
+        }
+        catch (Exception ex)
+        {
+            lastException = ex;
+            Console.Error.WriteLine($"[OobeStateService] LocalApplicationData failed: {ex.Message}");
+            stateDir = null;
+        }
+
+        // 策略2: 如果LocalApplicationData不行，使用用户的临时目录
+        if (stateDir == null)
+        {
+            try
+            {
+                var tempDir = Path.Combine(Path.GetTempPath(), "LanMountainDesktop", ".launcher", "state");
+                Directory.CreateDirectory(tempDir);
+                stateDir = tempDir;
+                Console.WriteLine($"[OobeStateService] Using TempPath: {stateDir}");
+            }
+            catch (Exception ex)
+            {
+                lastException = ex;
+                Console.Error.WriteLine($"[OobeStateService] TempPath failed: {ex.Message}");
+                stateDir = null;
+            }
+        }
+
+        // 策略3: 最后的兜底：使用当前用户的应用程序数据目录（和Launcher同目录
+        if (stateDir == null)
+        {
+            try
+            {
+                var launcherDir = AppContext.BaseDirectory;
+                stateDir = Path.Combine(launcherDir, ".launcher", "state");
+                Directory.CreateDirectory(stateDir);
+                Console.WriteLine($"[OobeStateService] Using Launcher directory: {stateDir}");
+            }
+            catch (Exception ex)
+            {
+                lastException = ex;
+                Console.Error.WriteLine($"[OobeStateService] All strategies failed! Last error: {ex.Message}");
+                // 如果所有策略都失败，抛出异常让上层处理
+                throw new InvalidOperationException("无法创建 OOBE 状态存储目录失败", lastException);
+            }
+        }
+
         _markerPath = Path.Combine(stateDir, "first_run_completed");
+        Console.WriteLine($"[OobeStateService] Initialized successfully, marker path: {_markerPath}");
     }
 
     public bool IsFirstRun()
     {
-        return !File.Exists(_markerPath);
+        try
+        {
+            return !File.Exists(_markerPath);
+        }
+        catch (Exception ex)
+        {
+            Console.Error.WriteLine($"[OobeStateService] Failed to check first run: {ex.Message}");
+            // 如果无法检查，默认视为首次运行，确保OOBE能显示
+            return true;
+        }
     }
 
     public void MarkCompleted()
     {
-        var dir = Path.GetDirectoryName(_markerPath);
-        if (!string.IsNullOrWhiteSpace(dir))
+        try
         {
-            Directory.CreateDirectory(dir);
-        }
+            var dir = Path.GetDirectoryName(_markerPath);
+            if (!string.IsNullOrWhiteSpace(dir))
+            {
+                Directory.CreateDirectory(dir);
+            }
 
-        File.WriteAllText(_markerPath, DateTimeOffset.UtcNow.ToString("O"));
+            File.WriteAllText(_markerPath, DateTimeOffset.UtcNow.ToString("O"));
+            Console.WriteLine("[OobeStateService] Marked first run as completed");
+        }
+        catch (Exception ex)
+        {
+            Console.Error.WriteLine($"[OobeStateService] Failed to mark completed: {ex.Message}");
+            // 如果无法写入也没关系，下次启动还会显示OOBE
+        }
     }
 }

LanMountainDesktop.Launcher/Services/UpdateEngineService.cs

@@ -217,6 +217,7 @@ internal sealed class UpdateEngineService
             snapshot.Status = "applied";
             SaveSnapshot(snapshotPath, snapshot);
             CleanupIncomingArtifacts();
+            // 清理旧版本，但保留最近3个版本以支持回滚
             CleanupDestroyedDeployments();
 
             return new LauncherResult