VS hangs for 1 minute on start debugging? Check for dead symbol paths!

I’ve just hit this again so I decided to share the solution in case anyone else hits this.

Symptom: Visual Studio freezes for about a minute after you hit F5 (but before the app actually starts), then suddenly unfreezes and happily proceeds to launch the app.

Cause: VS calls the Windows CreateFile function on one of the paths specified in Tools –> Options –> Debugging –> Symbols –> Symbol file (.pdb) locations and that location either doesn’t exist or can’t be accessed (e.g. due to misconfigured DNS settings).

Solution: Check that all network paths in the list above can be accessed normally.

If you launch ProcMon.exe before starting debugging and configure the filter to only monitor “devenv.exe”, Result = “BAD NETWORK PATH”, it should show you which CreateFile call causes a network timeout.


* http://support.microsoft.com/kb/951336
* http://social.msdn.microsoft.com/forums/en/vsdebug/thread/1ede20ce-b236-4361-8dcb-04189b607152