Hello guys,
If you’re like me, where every now and then your Spider or one of your Gadgeteer Boards suddenly refuses to deploy and you find yourself having to hit that reset button to make it deploy until you can no longer see your board in VS2010 nor in MFDeploy pushing you to re-flash the board well i may have a solution… at least this has worked for me so far…
If you get the error when you try to debug in VS2010 : Deploy Failed hit the reset button to get back to VS2010.
Next Go to your ProgramStarted() and put this line of code at the very beginning of it:
throw new Exception("test");
now hit the debug button and once it throws the exception, hit the continue button, next hit the stop button to return to VS2010 now delete the above code and hit debug again… suddenly VS2010 is happy and deploying… and after while if you get to that point again well repeat the process…
Please post back if this works for you… maybe it’ll help the team identify the issue and fix it once and for all 
thanks…