Visual Studio 2010 hangs on attach to process / debugging

Whenever I try to debug a Visual Studio 2010 web project, VS hangs, and ultimately crashes. This happens if I try to start the project using F5, or through Attach to Process, before the process list even appears.

Hitting F5 in, for exampl开发者_JS百科e, a Windows Form project works fine, but attach to process fails here too.

Any ideas on what can be causing this? Obviously attaching to the devenv.exe process won't work as I can't get the Attach to Process dialog to appear...

Oh, running W7 (x64), VS2010 SP1 (had same problems without SP1)

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In Solution Explorer there is a Show All Files icon (highlighted in the photo below):

Make sure it's turned off, When It's turned on, Visual Studio tries to index all the files in the solution and if you have a giant Solution it could take forever!

I hope this has helped someone :)

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Have you recently installed Mono and/or Mono Tools for VS2010? I found that to be the problem it my case. Not sure why, but it somehow got in the way.

Matthew

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In my case hangs when executable type was not correctly set, ex. Managed v4.0 and trying to attach to Native.