Install Visual Studio on the same computer as Visual Studio in 2013 "14" when CTP 14.0.21730.1 DP, a number of known issues.
While we expect that the Visual Studio "14" uninstall, and then click Visual Studio 2013 repair should resolve these problems, our security advice the installation of Visual Studio "14" VM, and VHD, a new computer or other non-production
test only on a computer that does not have Visual Studio installed in 2013. All of these Visual Studio side-by-side would be resolved soon.
This will prevent Visual Studio that you have installed an earlier version of Visual Studio installed on your computer "14" CTP are not installed in the block.
To disable will cause your computer to not recommend state blocks, the new values added to the registry "HKLM\SOFTWARE\Microsoft\DevDiv\vs\Servicing" position (as on a 64-bit Windows "HKLM\SOFTWARE\Wow6432Node\Microsoft\DevDiv\vs\Servicing").
The value name should beBlockerOverride, and can be any value type, and value data.