I have a DPR-1260 on raw TCP/IP port 9100, with an HP 6122 attached. This has been working fine for over a year.
Today I installed the VMware player on one Vista laptop to deliver a class where the labs are performed within a VM installed from DVD (not from a networked server). Once I'd installed, print jobs set to the printserver show up with an error after about 30 seconds. The job has to be cancelled.
Printing from other computers on the LAN still works, so the problem is not with the DPR-1260.
FWIW, I can see that the VM sees the printer too (ThinPrint detected and installed it), but it doesn't work from there either.
Has anyone else seen this behavior?