HP printers stop working

We have a number of HP deskjet printers of
various models which just stop working at random times. We have an NT4.0 network and I
have to reload the printer software each time
this problems occurs. I have downloaded and
used the latest software from HP for a number of the printers. These printers are all connected directly to indivual workstations and configured for “sharing”.
If anyone can give me ideas as to how to correct this problem, I would appreciate it.
Thanks.