Windows XP works fine, no problem there. But, there is no way to change the com port within the program. It automatically searchs for the 1st open port. However, it's been my experience that anything other than com 1 being open is a problem. Couple of thoughts:

1 Make sure you have any active sync SOFTWARE turned off - such as PDA software.

2 You could try TONTO, available here: [Link: giantlaser.com]. It's much less fussy about communications. If Tonto doesn't find the remote, I'd suspect a problem with either your adapter or the adapter's setup.