Can't print thru print server

Intermittently cannot print to a printer on the print server from a workstation. In our network several Win98 users can not print to our Windows NT print server. The printer becomes 'offline'
and you cannot even 'add' the same printer because it says that the computer name was not found. It is almost like our print server looses connection or either our users loose connection to that server. I reboot the server and sometimes this fixes it temporarily. I am hoping to get ideas to try to get this resolved.
Thank you,
Susan