After coming back from BULD 2014 yesterday, I wanted to get my desktop all updated with the Visual Studio 2013 Update 2 RC update, the Roslyn .NET Compiler CTP and the .NET Native Compiler.

The update to Visual Studio 2013 installed without a hitch as did the .NET Native Compiler, however the Roslyn vsix file errored out with the following error:
Project Roslyn VSIX failing to install

Guessing the error was related to my recent installing of Visual Studio 2010 to do ia64 development (more on that this week), I searched around and could only find one person reinstalling Visual Studio 2013 - definitely not something I was willing to do.

Checking in Windows Explorer with the Open With...Choose default program... option I noticed the Visual Studio 2010 Icon was associated with the Microsoft Visual Studio Version Selector:
Windows Explorer showing VS2010 Version Selector

I clicked More options, and then scrolled down to Look for another app on this PC:
Windows Explorer selecting Look for another app on this PC

I then navigated to my Visual Studio 2013 install (c:\Program FIles (x86)\Microsoft Visual Studio 12.0\Common7\IDE folder and selected VSIXInstaller.exe: Selecting Visual Studio 2013s VSIXInstaller

After selecting the Visual Studio 2013 VSIXInstaller application, Roslyn installed and I should note the icon in Windows Explorer (as expected) updated to the 2013 version:
Windows Explorer reflecting VS2013 VSIXInstaller Icon

For those having issues with a 2012 VSIX, simply use c:\Program FIles (x86)\Microsoft Visual Studio 11.0\Common7\IDE instead.

Hopefully that alleviated someone having to reinstall Visual Studio as it did for me.