feeding data through serial port on XP reboots PC

[1977BlackWolf]

Hello,

I have written a piece of software, in Delphi 4, that monitors a PCs serial ports for data that it fed in constantly from a piece of external hardware. It sits in the system tray and has no problem running on 95,98 and 2000.

However on XP it runs for a short while then reboots the PC!
It seems to see the serial connection as a serial mouse! How do I stop this happening?

I'm completely unfamiliar with XP so the answer may be obvious, but any ideas would be helpful.

Thanks for looking,

Ben