Re: variables corrupted

I have a VS 2005 C++ console application supporting MFC. Something's
happened since my last edit (it was working) and now I'm seeing
corrupted variables and Intellisense doesn't even recognize them.
For instance in the main function, if I Quickwatch nRetCode the IDE
says error CX0017 symbol not found.

int _tmain(int argc, TCHAR* argv[], TCHAR* envp[])
{
 int nRetCode = 0;
 // initialize MFC and print and error on failure
 if (!AfxWinInit(::GetModuleHandle(NULL), NULL, ::GetCommandLine(),
 0)) {
   // TODO: change error code to suit your needs
   _tprintf(_T("Fatal Error: MFC initialization failed\n"));
   nRetCode = 1;
}
   else
  {
   ////////////////////////////////////
   // Begin application here
  }
}

This is right at the beginning of the program, before any function
calls that I make. The only other code in the main module is a few
function declarations and #includes. I've commented everything else
out. Is there any way to figure out what's going on without
starting a new project and adding all the source one cpp at a time
until it breaks again?
Thanks