"Tip: If you are asking for help to troubleshoot a computer-related problem, please be sure to include all the necessary information (ie: operating system, model number, hardware, software, etc) that will help others identify your problem for a speedy resolution."

Given so little information in your post, its only guesses and I have no idea if I come close.

1. The install of XP may be incomplete. Some install XP but don't update BIOS, motherboard, video, audio and more drivers. It all "seems to work" so they find something like what you post.

2. Parallel port scanners are dead. Use such on the older OSes and be happy.

2a. If Windows 98 didn't work, it could be some combo or drivers or bad port.

But I can't help you since you told so little in your post. Also, you didn't tell what the scanner maker's support line told you to try.

Bob