>I may have to go back to the old PC :( thats not gonna make the boss happy.

It could still be a COM configuration problem on the Xp machine. Is there a modem on the Xp machine that might be using the same interrupt(IRQ)? If I recall, COM1/COM3 share IRQ4 while COM2/COM4 share IRQ3.

Also, what I always do is go into BIOS and check and make sure all COM ports are configured to specs. I remember a war story a few years back. Our PC technician built a new machine from bare-bones. His definition of a finished job was, "If it boots up I'm done!". Needless to say, the PC was riddled with problems--COM ports not turned on in the BIOS to incompatible hardware.

Anyway, the symptoms that you are describing could be a IRQ conflict, and the only way to make sure is to go into the BIOS and check. Also, it may be necessary to pull out the modem--if not built into the motherboard--just to make sure.

HTH and good luck!

--Paul