NT wkstn keeps losing printers overnight

I can’t for the life of me figure this one out. One of the workstations on my network has 2 local printers and 2 networked printers. In the evenings, this particular user lock’s down the workstation, but doesn’t log off or shut down.

For the last couple of weeks, when he comes into the office, all of his printers are gone. Once he re-boots his box everything is fine, but it starts all over again the following morning. I’ve got it narrowed down to something in the RPC service, but can’t quite figure it out.

I’d appreciate some help on this one. Workstation is running sp6 with 64Mb RAM on a 233Mhz PII. (no jokes about the age of the boxes please!)