I have an interesting (and incredibly frustrating) problem where my application runs fine, but ONLY when a debugger is attached to it.

I can build in both Debug or Release and double clicking the execuable causes it to crash before the window is drawn. However if I launch from the IDE (VS2010), again in both Debug or Release mode, the application runs perfectly fine.

I'm at a loss and have no idea how to debug in this situation.

All suggestions welcome.

I am using VS2010 in Windows 7, C++ with MFC. This is an application which has been migrated from VC++ 6 to VS2010. Note, it works perfectly when built from VC++ 6.