Ipod nano not showing up in ITunes 9.2.1.5 on Windows XP

My mom has a 4GB 1st generation nano and I've been trying to add new songs via iTunes. I have tried all the suggestions for "iPod appears in Windows but not iTunes" article and I still cannot get her ipod to show up in iTunes. The computer I'm trying to get the ipod to work on is a desktop computer running Windows XP. I tried my mom's ipod on my laptop computer thinking maybe it was a problem with the ipod or the cable. It worked just fine. I have Windows 7 running an identical version of iTunes. I'm a grad student and I'm just home for the summer. I need solve this problem and fix my mom's ipod so it will work on her own computer while I'm away. Is there anything else I can do to get her iPod to show up in iTunes?