我安装VS2017时报错界面：
点击view log:我的出错日志是：
The product failed to install the listed workloads and components due to one or more package failures.
Incomplete workloads
Desktop development with C++ (Microsoft.VisualStudio.Workload.NativeDesktop,version=15.0.26228.0)
Visual Studio extension development (Microsoft.VisualStudio.Workload.VisualStudioExtension,version=15.0.26208.0)
Incomplete components
C# and Visual Basic (Microsoft.VisualStudio.Component.Roslyn.LanguageServices,version=15.0.26208.0)
C++ profiling tools (Microsoft.VisualStudio.Component.VC.DiagnosticTools,version=15.0.26208.0)
Graphics debugger and GPU profiler for DirectX (Microsoft.VisualStudio.Component.Graphics.Tools,version=15.0.26208.0)
IntelliTrace (Microsoft.VisualStudio.Component.IntelliTrace.FrontEnd,version=15.0.26208.0)
Profiling tools (Microsoft.VisualStudio.Component.DiagnosticTools,version=15.0.26208.0)
Static analysis tools (Microsoft.VisualStudio.Component.Static.Analysis.Tools,version=15.0.26208.0)
VC++ 2017 v141 toolset (x86,x64) (Microsoft.VisualStudio.Component.VC.Tools.x86.x64,version=15.0.26208.0)
Visual Studio extension development prerequisites (Microsoft.VisualStudio.ComponentGroup.VisualStudioExtension.Prerequisites,version=15.0.26208.0)
Visual Studio SDK (Microsoft.VisualStudio.Component.VSSDK,version=15.0.26208.0)
You can search for solutions using the information below, modify your selections for the above workloads and components and retry the installation, or remove the product from your machine.
Following is a collection of individual package failures that led to the incomplete workloads and components above. To search for existing reports of these specific problems, please copy and paste the URL from each package failure into a web browser. If the issue has already been reported, you can find solutions or workarounds there. If the issue has not been reported, you can create a new issue where other people will be able to find solutions or workarounds.
Package 'Microsoft.VisualCpp.Redist.14,version=14.10.25008,chip=x64' failed to install.
Search URL: https://aka.ms/VSSetupErrorReports?q=PackageId=Microsoft.VisualCpp.Redist.14;PackageAction=Install;ReturnCode=1638
Impacted workloads
Desktop development with C++ (Microsoft.VisualStudio.Workload.NativeDesktop,version=15.0.26228.0)
Visual Studio extension development (Microsoft.VisualStudio.Workload.VisualStudioExtension,version=15.0.26208.0)
Impacted components
C# and Visual Basic (Microsoft.VisualStudio.Component.Roslyn.LanguageServices,version=15.0.26208.0)
C++ profiling tools (Microsoft.VisualStudio.Component.VC.DiagnosticTools,version=15.0.26208.0)
Graphics debugger and GPU profiler for DirectX (Microsoft.VisualStudio.Component.Graphics.Tools,version=15.0.26208.0)
IntelliTrace (Microsoft.VisualStudio.Component.IntelliTrace.FrontEnd,version=15.0.26208.0)
Profiling tools (Microsoft.VisualStudio.Component.DiagnosticTools,version=15.0.26208.0)
Static analysis tools (Microsoft.VisualStudio.Component.Static.Analysis.Tools,version=15.0.26208.0)
VC++ 2017 v141 toolset (x86,x64) (Microsoft.VisualStudio.Component.VC.Tools.x86.x64,version=15.0.26208.0)
Visual Studio extension development prerequisites (Microsoft.VisualStudio.ComponentGroup.VisualStudioExtension.Prerequisites,version=15.0.26208.0)
Visual Studio SDK (Microsoft.VisualStudio.Component.VSSDK,version=15.0.26208.0)
Log
C:\Users\Administrator\AppData\Local\Temp\dd_setup_20200210190712_116_Microsoft.VisualCpp.Redist.14.log
Details
Command executed: "C:\ProgramData\Microsoft\VisualStudio\Packages\Microsoft.VisualCpp.Redist.14,version=14.10.25008,chip=x64\VC_redist.x64.exe" /q /norestart /log "C:\Users\Administrator\AppData\Local\Temp\dd_setup_20200210190712_116_Microsoft.VisualCpp.Redist.14.log"
Return code: 1638
Return code details: Another version of this product is already installed. Installation of this version cannot continue. To configure or remove the existing version of this product, use Add/Remove Programs on the Control Panel.
重点在最后三句，已经安装了一个新的了。
打开控制面板，可以看到这一项已经安装了，
并且版本比我的2017要新。把这一项删除后再modify安装一次就可以了。