SOLVED Could not load file or assembly Microsoft.VisualStudio.ManagedInterfaces
One of our developer was unable to load any project in Visual Studio 2010, the error was 'Could not load file or assembly 'Microsoft.VisualStudio.ManagedInterfaces, Version=8.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a'
I checked c:\WINDOWS\assembly\GAC_MSIL and found the folder 'Microsoft.VisualStudio.ManagedInterface.9.0.0', it was clear that Visual Studio was looking for version 8 so I copied the Microsoft.VisualStudio.ManagedInterfaces.dll from one of the computers to this computer.
Once copied to the C:\, I opened command prompt and went to 'C:\Program Files\Microsoft SDKsWindows\v7.0A\bin'
At this prompt I typed gacutil -i c:\Microsoft.VisualStudio.ManagedInterfaces.dll and it gave the message that the dll was successfully loaded in cache
I closed Visual Studio and reopened, the project loaded fine without any errors.