Sorry people. This is just a note to myself because every few months I come across the same problems with a new development build.

Failed to access IIS metabase:

aspnet_regiis -i

Mutex Could not be Created:

Solution posted here by Joao Morais.

I have got the same issue. It seems like Visual studio 2005 and the web application pool running ASP.NET 2.0 are having a conflict over the temporary folder.

The workaround I have got for now is:

• If you have visual studio 2005 is open, close it
• Go to the ASP.NET temporary folder for v2.0 of the framework
  <Windows dir>\Microsoft.Net\Framework\v2.0<extra numbers>\Temporary ASPNET pages
• Remove the folder for your application (or all of them)
• Reset IIS (on a command line window, iisreset) [not always needed, but I had to use it sometimes]
• First Browse your page from IE (http://localhost/your app)
• Then reopen Visual studio