I had a strange error consistently appear when I launched "Microsoft SQL Server Management Studio". Unable to cast COM object of type 'System.__ComObject' to interface type 'Microsoft .VisualStudio .OLE .Interop .IServiceProvider'. Exception from HRESULT: 0x80004002 (E_NOINTERFACE))
Apparently the registry got corrupted. After Googling for 30 minutes, I found the solution. A DLL driver needs to be unregistered and registered again, and then the error goes away. Ah - the joys of Windows programming.
The steps to resolve the error is:
1. Right click on "Command prompt" and choose "Run as administrator"
2. cd /d C:\Windows\system32
3. regsvr32.exe /u actxprxy.dll
4. regsvr32.exe actxprxy.dll