Originally posted by elim
actually....I thought it was working, because when I would execute the program again, the same window would reappear (if minimized) or would blink if it was already restored on my desktop. But when I look in TaskManager, I see multiple instances of MyAppTitle.exe running, even though I only see one window for my application. Again, this is only in release mode...Any help would be great, thanks.
I pasted your code into a simple app, and it seems to work just fine in release mode.
Perhaps you could do the same thing I did - put the code into a new project and see if it works as expected. If so, the problem is elsewhere in the original project. If it does not work, post your sample project and someone can take a look at it.

I might note that it is helpful if you use the CODE tags when posting code...

Also - the comment in the code:
//create a mutex to keep this app a single instance app
//don't worry about return HANDLE because it's auto reclaimed by OS
//on process termination.
indicates poor programming practice.