There was that old problem of blown USB ports on PDAs. Fix.
Go get the SERIAL DOCK or SERIAL SYNC CABLE.
It's so far out of warranty that I doubt it can be covered.
There's also a recurring issue with drivers on the PC. The owner will claim "I didn't change a thing" but I just go ahead and install the motherboard chipset drivers and my luck is that many times it will fix it. I'll check back tomorrow if you decide to reveal what the host PC is.