Visual Studio extension conflict when removing a project

Question

After I save the changes of a solution and then remove an existing project, I'll get the following error message:

The operation could be completed. Not implemented.

Then I launched devenv.exe /Log and able to reproduce the problem and the errors are:

Extension will not be loaded because an extension with the same ID 'Microsoft.Windows.DevelopmentKit.Desktop' is already loaded at 
C:\PROGRAM FILES (X86)\COMMON FILES\MICROSOFT\EXTENSIONMANAGER\EXTENSIONS\MICROSOFT\WINDOWS KITS\8.0\DESKTOP SDK\
C:\PROGRAM FILES (X86)\COMMON FILES\MICROSOFT\EXTENSIONMANAGER\EXTENSIONS\MICROSOFT\WINDOWS KITS\8.1\DESKTOP SDK\

Extension will not be loaded because an extension with the same ID 'Microsoft.WinJS' is already loaded at 
C:\PROGRAM FILES (X86)\MICROSOFT SDKS\WINDOWS\V8.1\EXTENSIONSDKS\MICROSOFT.WINJS.SHARED\VSIX\
C:\PROGRAM FILES (X86)\MICROSOFT SDKS\WINDOWS\V8.0\EXTENSIONSDKS\MICROSOFT.WINJS.SHARED\VSIX\

It looks like it's trying to load two extensions but with different versions. I believe they are the Microsoft Advertising SDK for Windows 8.1 and Microsoft Advertising SDK for Windows Phone 8.1 but even if I launch VS 2012 with Admin, the Uninstall button is greyed out for me. I don't see them in the Add/Remove Programs either. So how can I get rid of this error?

A side note, I have both VS 2012 and VS 2013 installed and I had to do a repair on VS 2012 after VS 2013 was installed.

Answer 1

I had the same problem with Microsoft Windows Development Kit: two errors every time at Visual Studio start with description in the %AppData%\Roaming\Microsoft\VisualStudio\14.0\ActivityLog.xml

Sometimes (I think every time) Visual Studio Updater or Installer (when you try to install other version of VS) does not remove already installed version of a VS module.

In my case I had the second WDK with older version but installed after the newer one. I manually uninstalled the older version of Microsoft Windows Development Kit and problem with Visual Studio was solved.