As usuall printing problems…

I am running win2k server with XP workstations, I have a few workstations that you have to log off and on to be able to print … all the printers are controlled by a logon script and it only seems to be happening at a few different machines not allof them. As printing either works or it doesn’t I have not had much experience in trouble shooting this intermitant problem, any suggestions would be helpful. OH btw the printers show up in their lists but the device not available error is what comes up on trying to print.