diff --git a/auto-setup.ps1 b/auto-setup.ps1
index f296883..0c42ee4 100644
--- a/auto-setup.ps1
+++ b/auto-setup.ps1
@@ -20,7 +20,7 @@ param(
 $ErrorActionPreference = "Stop"
 
 # ─── 版本号 (每次更新递增, build.ps1 自动读取) ──────
-$BWVersion = "3.0.2"  # +ExecutionPolicy +WM_SETTINGCHANGE 广播 +.claude.json 预填跳过 v2.0.1 登录画面
+$BWVersion = "3.0.3"  # +PS7 MSI 直链兜底 (Win10 无 winget 仍能装 pwsh, 避免跌落到 PS 5.1)
 
 # DryRun 模式日志标记
 if ($DryRun) { $global:BWDryRun = $DryRun } else { $global:BWDryRun = $null }
@@ -779,7 +779,7 @@ $deps = @(
     # 核心依赖 (缺失则尝试自动安装)
     @{ Name = "Node.js";       Cmd = "node";   WingetId = "OpenJS.NodeJS.LTS";              NpmPkg = $null;  PipPkg = $null; Core = $true }
     @{ Name = "Git";           Cmd = "git";    WingetId = "Git.Git";                        NpmPkg = $null;  PipPkg = $null; Core = $true }
-    @{ Name = "PowerShell 7";  Cmd = "pwsh";   WingetId = "Microsoft.PowerShell";           NpmPkg = $null;  PipPkg = $null; Core = $false }
+    @{ Name = "PowerShell 7";  Cmd = "pwsh";   WingetId = "Microsoft.PowerShell";           NpmPkg = $null;  PipPkg = $null; Core = $true; MsiUrl = "https://github.com/PowerShell/PowerShell/releases/download/v7.4.6/PowerShell-7.4.6-win-x64.msi" }
     @{ Name = "Claude Code";   Cmd = "claude"; WingetId = $null;                            NpmPkg = "@anthropic-ai/claude-code"; PipPkg = $null; Core = $true }
     # Python 移到可选依赖 (不在此列表, 由 line 753 单独处理)
 )
@@ -808,6 +808,31 @@ foreach ($dep in $deps) {
                 Log-Fail "$($dep.Name) 安装失败: $_"
             }
         }
+        # v3.0.3: winget 缺席/失败时, 用 MSI 直链兜底 (主要针对 Win10 21H1 及更早版本无 winget / AppInstaller 过老)
+        if (-not (Test-Cmd $dep.Cmd) -and $dep.MsiUrl) {
+            Log-Warn "$($dep.Name) winget 路径失败, 改走 MSI 直链..."
+            $msiPath = Join-Path $env:TEMP "bw-$($dep.Cmd)-installer.msi"
+            try {
+                # TLS 1.2 强制 (Win10 默认 TLS 1.0/1.1 访问 GitHub 会断)
+                [Net.ServicePointManager]::SecurityProtocol = [Net.ServicePointManager]::SecurityProtocol -bor [Net.SecurityProtocolType]::Tls12
+                Log-Info "  下载 $($dep.MsiUrl.Substring($dep.MsiUrl.LastIndexOf('/')+1))"
+                Invoke-WebRequest -Uri $dep.MsiUrl -OutFile $msiPath -UseBasicParsing -TimeoutSec 300 -EA Stop
+                if ((Get-Item $msiPath).Length -lt 1MB) { throw "MSI 下载不完整: $((Get-Item $msiPath).Length) bytes" }
+                Log-Info "  安装 MSI (静默, 需 1-2 分钟)..."
+                $p = Start-Process "msiexec.exe" -ArgumentList "/i", "`"$msiPath`"", "/quiet", "/qn", "/norestart", "ADD_PATH=1" -Wait -PassThru -NoNewWindow
+                Remove-Item $msiPath -Force -EA SilentlyContinue
+                $env:Path = [System.Environment]::GetEnvironmentVariable("Path","Machine") + ";" + [System.Environment]::GetEnvironmentVariable("Path","User")
+                # PS7 MSI 默认装到 %ProgramFiles%\PowerShell\7\pwsh.exe, 强制补 PATH
+                $ps7Dir = "$env:ProgramFiles\PowerShell\7"
+                if ((Test-Path "$ps7Dir\pwsh.exe") -and ($env:Path -notlike "*$ps7Dir*")) { $env:Path = "$ps7Dir;$env:Path" }
+                if (Test-Cmd $dep.Cmd) {
+                    Log-OK "$($dep.Name) MSI 安装成功 (exit $($p.ExitCode))"
+                    $installed += $dep.Name
+                } else {
+                    Log-Fail "$($dep.Name) MSI 安装后仍找不到 pwsh (exit $($p.ExitCode))"
+                }
+            } catch { Log-Fail "$($dep.Name) MSI 直链失败: $_" }
+        }
         elseif ($dep.NpmPkg -and (Test-Cmd "npm")) {
             try {
                 $r = Run-CmdWithUI "npm" @("i", "-g", $dep.NpmPkg) "npm 安装 $($dep.Name)" 120000