New printer error

Hi there,
Thanks for reading. We are running W2k on our print server (Dell PowerEdge 4400/600Mhz/1GBram) with 20 networked printers serving a high school. Everything was fine til recent. Of a sudden, library and two labs using 4050 printers get error:

Device settings cannot be displayed. The driver for the specified printer is not installed. Only spooler properties will be displayed. Do you want to install the driver now?"

This occurs when printing from IE or Notepad but Word prints without a problem. We also see the same error when trying to directly access the properties of the printer when logged in at the server.

Notepad complains about missing dll (HPBF002K.DLL). Found the dll both on clients and server. Both were the same size (450k) Tried copying/pasting to no avail.

I have deleted the printer and the drivers from the server (Printers folder\Server properties) and reinstalled with the driver dated 9/19/2003 with same result.

Any ideas?

Thanks in advance!
Bob