Visual Studio 2010 Beta2 says "The application cannot start."

We have been having this issue with Visual Studio 2010 Beta2. It just stops loading. For some it stops loading unless you load it via loading a solution, others it's the opposite.

We can't move to the RC2 until we it supports Silverlight 4 properly..

The solution?

We have had some success by just loading up a visual studio command prompt and running:
devenv /ResetSettings

UPDATE:
Also try:
devenv /reset
devenv /resetuserdata


Give it a go. Let me know how you get on :)
(It might also be worth backing up your currentsettings.xml file first)