win10无法安装vs2019，反复下载验证

查询temp里的日志，以下是日志内容：
VisualStudio Bootstrapper:2021/7/13 21:58:33: DownloadURL = https://aka.ms/vs/15/release/installer
VisualStudio Bootstrapper:2021/7/13 21:58:33: InstallLocation = C:\Program Files (x86)\Microsoft Visual Studio\Installer
VisualStudio Bootstrapper:2021/7/13 21:58:33: OfflineFilePath =
VisualStudio Bootstrapper:2021/7/13 21:58:33: LayoutLocation =
VisualStudio Bootstrapper:2021/7/13 21:58:33: ExecutableArguments = /finalizeInstall install --in "C:\ProgramData\Microsoft\VisualStudio\Packages_bootstrapper\vs_setup_bootstrapper_202107132158334625.json" --locale zh-CN --activityId "c9863d6f-0018-4efe-9e47-e95aed59e532"
VisualStudio Bootstrapper:2021/7/13 21:58:33: OSVersion = Microsoft Windows NT 10.0.19042.0
VisualStudio Bootstrapper:2021/7/13 21:58:33: Starting to detect the existing VS and .Net...
VisualStudio Bootstrapper:2021/7/13 21:58:33: Finished detecting the existing VS and .Net
VisualStudio Bootstrapper:2021/7/13 21:58:35: Beginning file download. File = https://aka.ms/vs/15/release/installer.
VisualStudio Bootstrapper:2021/7/13 21:58:35: Download requested: https://aka.ms/vs/15/release/installer
VisualStudio Bootstrapper:2021/7/13 21:58:35: Attempting download 'https://aka.ms/vs/15/release/installer' using engine 'WebClient'
VisualStudio Bootstrapper:2021/7/13 21:58:39: Uri 'https://aka.ms/vs/15/release/installer' redirected to 'https://download.visualstudio.microsoft.com/download/pr/67f7bfaa-2635-43d9-ba82-26564f458881/F23BD543D19EC1F9009C377D0C3AFBC07930798A838FF69AB36AEAA8D12FA7F3/vs_installer.opc'
VisualStudio Bootstrapper:2021/7/13 21:58:42: Package signature verification threw exception: 终结点映射器中没有更多的终结点可用。
, for path: C:\ProgramData\Microsoft\VisualStudio\Packages_bootstrapper\vs_installer\p.4zc\vs_installer.opc"
VisualStudio Bootstrapper:2021/7/13 21:58:42: Package signature verification threw exception: 终结点映射器中没有更多的终结点可用。
, for path: C:\ProgramData\Microsoft\VisualStudio\Packages_bootstrapper\vs_installer\p.4zc\vs_installer.opc"
VisualStudio Bootstrapper:2021/7/13 21:58:42: Caught Exception: Type = InvalidSignatureException, Message = Package signature verification threw exception: 终结点映射器中没有更多的终结点可用。
, for path: vs_installer.opc", StackTrace =
VisualStudio Bootstrapper:2021/7/13 21:58:42: Package signature verification threw exception: 终结点映射器中没有更多的终结点可用。
, for path: vs_installer.opc"
VisualStudio Bootstrapper:2021/7/13 21:58:42: Download failed using WebClient engine. Microsoft.VisualStudio.Setup.Security.InvalidSignatureException: Package signature verification threw exception: 终结点映射器中没有更多的终结点可用。
, for path: vs_installer.opc"
在 Microsoft.VisualStudio.Setup.Download.DownloadManager.DownloadWithRetry(IDownloadEngine[] engines, Uri uri, Stream outputStream, ProgressUpdateCallback progress, CancellationToken cancellationToken, DownloadContext downloadContext, Boolean verifySignature)
VisualStudio Bootstrapper:2021/7/13 21:58:42: Sleeping 5000 milliseconds before retrying download.
VisualStudio Bootstrapper:2021/7/13 21:58:47: Attempting download 'https://aka.ms/vs/15/release/installer' using engine 'Bits'
VisualStudio Bootstrapper:2021/7/13 21:58:58: Canceling job 'VsBitsDownloadJob - -406993119'.
VisualStudio Bootstrapper:2021/7/13 21:58:58: User Cancelled Download
VisualStudio Bootstrapper:2021/7/13 21:58:58: Bootstrapper cancelled.
这次是我自己取消的，不取消会重复五六次然后退出下载，请问这种情况该如何解决

Host文件里添加
122.188.0.118 download.visualstudio.microsoft.com

之后命令提示符运行几次ipconfig /flushdns

速度杠杠滴