A VB 5 routine that attempts to open all the com ports and catches any
errors to determine which com ports are available finds all the available
com ports fine, but often it also stops the mouse working completely
(especially with an intellimouse) - and a computer reboot is the only
solution I can find.  Does anybody know of a simple API method of finding
which comports the computer has, and whether another process is using them
- without interferening with that other process?

Thanks,
Grant Kassell