I un-installed VS Studio 2010 dues to storage capacity issues, after I had un-installed I could not longer use SQL Server Management Studio, the database was running fine, but I could not open SSMS. I ran the repair on the SQL Server but that did not fix the issue. I installed and repaired the suggested dependency on VS 2010 Shell (Isolated), but that still had not affect.
I decided to go down the risky road and delete the registry key. There were suggestions of deleting 13, but I only had 11 and 12. So I renamed it first 11_Delete, no change, then 12_Delete and that was the problem. Once I restarted SSMS it created the folder 12_Config again and then I deleted the folder I had renamed.
Computer\HKEY_CURRENT_USER\Software\Microsoft\SQL Server Management Studio\12.0_Config
