🚀 go-pugleaf

You didn't think I'd get through a week without having an insoluble problem
did you?

At school today, one of the Macs on our network (of 4 machines, connected
by AppleTalk) suddenly wouldn't print - it said it couldn't find the
printer (a Hewlett Packard Deskjet 550C). (The network only exists to share
the printer - no file sharing etc. goes on).

The Macs are Performa 5260s, running system 7.5.3. I should also mention
that I suspect the PRAM batteries have just run out on all 4 (the dates are
now 1956 and the times are all wrong, since we came back after the
holidays). But the other 3 Macs on the system can still print with no
problems, despite the same date/time symptoms so I don't think that can be
the cause of this problem. The machines haven't been moved, and no kids
have used them without close supervision. They're protected by At Ease, and
no-one except the teacher in charge of them has been in at admin level.

The strange thing is that when you go into the Chooser, the icon for the DW
550C (Apple Talk) appears in the LH window, but if you click on it it does
*not* appear in the RH window. What *does* happen is an invitation appears
at the top of the (empty) RH window saying "Select a DeskWriter 550". I
don't understand this at all - it doesn't happen on the other machines.
Clicking on the *other* DW 550C icon (the Serial one) does make that icon
appear in the RH window and the invitation to choose the port appears.

I've tried:
- checking all connections, and restarting 
- running Norton Utilities over the disk, and restarting
- rebuilding the desktop, and restarting
- deleting and reinstalling the DW 550C (Apple Talk) extension, and
restarting
- deleting and reinstalling the Chooser, and restarting
- considered deleting preferences, but couldn't find an appropriate file to
delete


Help!!!