I have a 4-5 year old NEC Lavie laptop, with XP home edition (Japanese version on a Japanese OS).
I have seen problems on and off (yeah, sporadic! Just what a troubleshooter likes to hear, eh?!) with any of the USB ports. It has 4.
One problem is that it sometimes fails to recognize the connection to my Canon printer, despite replacing the cable. As a result, it may completely not make a connection or it might and then after any number of pages have successfully printed, it might stop connecting. Rebooting the laptop and turning the printer off/on a few times (annoying as heck) eventually resolves the problem.
Another related (?) problem has come up fairly recently when I use a USB drive. My main use is with Word documents. In the middle of using Word, the computer doesn't recognize the USB drive anymore, shows it is empty, and does not allow any document in progress to be saved on it. Usually, it even causes Word to shut down. Firing up Word again sometimes works, sometimes doesn't unless I reboot the computer (the usual fix). I can't even pull out the USB and reinsert it to regain a connection unless I reboot.
Plenty of free memory space on the USB drive, by the way.
Check out NEC's support site and see if they have any chipset updates for your particular model. If so, updating the chipset usually "resets" the USB ports. If that doesn't work, I would guess that it is a hardware related issue, especially seeing how old the laptop is. Never the less, try the chipset update and let us know.
Thanks for the advice. Unfortunately, I could not locate any kind of chipset. This is a Japanese model (Lavie C LC500/4), and inputting Lavie into the search function calls up Japanese-only sites. I can't read them, and my Japanese wife doesn't understand them. What's worse, she is a technophobe and won't call the service center. Typical "can't help it" attitude of most Japanese people.
As for any age-relatedness to this being a hardware problem, what do you think if I tell you this has been giving problems almost since the day we bought it?