Visual Studio 2015 RC Community will not install, says it is already installed

Question

As the title implies, I am not able to install Visual Studio 2015 RC Community, and I keep getting the following errors. For the record, I am on Windows 8.1 Professional.

Answer 1

I had a similiar issue and found finally as cause entries under

HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Microsoft\DevDiv\vs\Servicing\14.0. To modify/delete this entries (or the key itself) solved (for me) the problem.

By K.Hoffmann