I've looked around quite a bit, but I have yet to find a free way to monitor a serial port (without opening or blocking it from other applications), that works on Windows 7 64-bit.

Even Microsoft's own Portmon does not work. A few posts have talked about running it in compatibility mode, but it doesn't work for me. I've tried compatibility mode for Windows XP service pack 2 and 3 (the only ones available on the drop-down list), and neither allow it to function.

So yeah, is there any way of monitoring a serial port for Windows 7 64-bit?