上周五日常檢查系統更新（強迫症晚期）
出現一項更新：2021-09 .NET 5.0.10 Update for x64 Client (KB5006192)
等待更新后，提示這樣一個錯誤：0x80070643
目前在網上，暫無搜到相關解決方案，但我根據該鏈接給出的腳本內容中的路徑 SoftwareDistributionDownload 得到啟發：DISM命令手動安裝解決Win10安裝更新失敗錯誤代碼0x80070643的問題
根據這個路徑，找到 C:\Windows\SoftwareDistribution\Download\Install 目錄，看到該目錄下有個 windowsdesktop-runtime-5.0.10-win-x64.exe，
雙擊運行 windowsdesktop-runtime-5.0.10-win-x86.exe ，報錯：
點擊查閱日志文件：
[20E8:1B98][2021-11-08T09:55:19]i001: Burn v3.14.0.4118, Windows v10.0 (Build 19042: Service Pack 0), path: C:\Windows\Temp\{7EE31960-AD75-473A-85E0-37918BF763D3}\.cr\windowsdesktop-runtime-5.0.10-win-x86.exe
[20E8:1B98][2021-11-08T09:55:19]i000: Initializing string variable 'DOTNETHOME' to value '[ProgramFilesFolder]dotnet'
[20E8:1B98][2021-11-08T09:55:19]i000: Initializing string variable 'BUNDLEMONIKER' to value 'Microsoft Windows Desktop Runtime - 5.0.10 (x86)'
[20E8:1B98][2021-11-08T09:55:19]i000: Initializing string variable 'PRODUCT_NAME' to value 'Microsoft Windows Desktop Runtime - 5.0.10 (x86)'
[20E8:1B98][2021-11-08T09:55:19]i000: Initializing string variable 'LINK_PREREQ_PAGE' to value 'https://go.microsoft.com/fwlink/?linkid=846817'
[20E8:1B98][2021-11-08T09:55:19]i009: Command Line: '-burn.clean.room=C:\Windows\SoftwareDistribution\Download\Install\windowsdesktop-runtime-5.0.10-win-x86.exe -burn.filehandle.attached=592 -burn.filehandle.self=588'
[20E8:1B98][2021-11-08T09:55:19]i000: Setting string variable 'WixBundleOriginalSource' to value 'C:\Windows\SoftwareDistribution\Download\Install\windowsdesktop-runtime-5.0.10-win-x86.exe'
[20E8:1B98][2021-11-08T09:55:19]i000: Setting string variable 'WixBundleOriginalSourceFolder' to value 'C:\Windows\SoftwareDistribution\Download\Install\'
[20E8:1B98][2021-11-08T09:55:19]i000: Setting string variable 'WixBundleLog' to value 'C:\Users\ADMINI~1\AppData\Local\Temp\Microsoft_Windows_Desktop_Runtime_-_5.0.10_(x86)_20211108095519.log'
[20E8:1B98][2021-11-08T09:55:19]i000: Setting string variable 'WixBundleName' to value 'Microsoft Windows Desktop Runtime - 5.0.10 (x86)'
[20E8:1B98][2021-11-08T09:55:19]i000: Setting string variable 'WixBundleManufacturer' to value 'Microsoft Corporation'
[20E8:5BF4][2021-11-08T09:55:19]i000: Setting numeric variable 'WixStdBALanguageId' to value 1033
[20E8:5BF4][2021-11-08T09:55:19]i000: Setting version variable 'WixBundleFileVersion' to value '5.0.10.30418'
[20E8:1B98][2021-11-08T09:55:19]i100: Detect begin, 4 packages
[20E8:1B98][2021-11-08T09:55:19]i102: Detected related bundle: {7ce2617d-0a0a-4f61-8e5a-96f7bfca6fdd}, type: Upgrade, scope: PerMachine, version: 5.0.11.30524, operation: Downgrade
[20E8:1B98][2021-11-08T09:55:19]i101: Detected package: dotnet_runtime_5.0.10_win_x86.msi, state: Absent, cached: Complete
[20E8:1B98][2021-11-08T09:55:19]i101: Detected package: dotnet_hostfxr_5.0.10_win_x86.msi, state: Absent, cached: Complete
[20E8:1B98][2021-11-08T09:55:19]i101: Detected package: dotnet_host_5.0.10_win_x86.msi, state: Absent, cached: None
[20E8:1B98][2021-11-08T09:55:19]i101: Detected package: windowsdesktop_runtime_5.0.10_win_x86.msi, state: Absent, cached: Complete
[20E8:1B98][2021-11-08T09:55:19]i052: Condition '((VersionNT > v6.1) OR (VersionNT = v6.1 AND ServicePackLevel >= 1))' evaluates to true.
[20E8:1B98][2021-11-08T09:55:19]i199: Detect complete, result: 0x0
[20E8:5BF4][2021-11-08T09:55:21]e000: Error 0x80070666: Cannot install a product when a newer version is installed.
如圖提示，安裝了更新的版本，導致當前安裝不成功。Cannot install a product when a newer version is installed.
到控制面板->程序和功能，找到 Microsoft Windows Desktop Runtime - 5.0.10 (x86)，卸載，然后 Windows Update 點重試。
接着可能還是會出現更新失敗，重復以上步驟，找到如下exe，逐個依次重復以上步驟，直到完全成功。
此時，恭喜你全部安裝了 老版本的 .NET 5。
- dotnet-runtime-5.0.10-win-x86.exe
- windowsdesktop-runtime-5.0.10-win-x64.exe
- dotnet-sdk-5.0.401-win-x86.exe
- windowsdesktop-runtime-5.0.10-win-x86.exe
- aspnetcore-runtime-5.0.10-win-x64.exe
- dotnet-runtime-5.0.10-win-x64.exe
- dotnet-sdk-5.0.401-win-x64.exe
- dotnet-sdk-5.0.207-win-x64.exe
- aspnetcore-runtime-5.0.10-win-x86.exe
- dotnet-sdk-5.0.207-win-x86.exe
PS: 可能是任意以上exe，都有類似問題，甚至需要每次逐個卸載相對應的最新版本，后重裝老版本，然后將 Windows Update 成功后，再自行安裝最新版本。
該問題主要出現在，電腦安裝了 Visual Studio 2019 最新版本的開發者。
Windows Update 成功后，不要手動升級 Microsoft Windows Desktop Runtime 和 Microsoft ASP.NET Core Runtime 到最新版本 5.0.11，
否則 Windows Update 又會提示 KB5006192 更新，並且更新還是會失敗。