Your out of luck.

The F12 key triggering a breakpoint is a biult in feature of the win 32 debugging subsystem. When ever you have any debugger attached to a process via the win32 debugginDetg API, F12 will always trigger a breakpoint. This is implemented at the kernal level, like Ctl-Alt-Del.

Add code to detect when a debugger is attached to a process (IsDebuggerPresent), and just remap what F12 does in the application while the debugger is attached.

Also under windows XP, it is posible to unattach a debugger without killing the debugged process.