Network printer going offline

4 network printers in a small LAN OF about 40 PC,S started going off line each time any from any user from any location tries to print.
The problem started after a sudden shut down of the NT4.0 Print server controlling these printers.
The printersare HP Laserjet 4050n directly connected to the network via the jetlink and rj45 port.

The network protocol is TCP/IP and all the printers can be succesfully pinged from any user location using their IP address.

These printers still print after putting them back on line by right clicking the printer icon in the printers window.

What can be done to resolve this problem.
Thanks.