LaserJet MFP M125nw won't print

[addisongeek]

I have a customer who owns the LaserJet Pro MFP M125nw, and it just quit printing from one computer.  She had it connected via USB, so I downloaded and installed the latest software.  No matter how many different times I installed it, the printer would not print even the internal test page.  I even tried 3 different USB ports to no avail.  The print spooler has been stopped, the printer folder contents deleted, and the spooler started again with no success.

I finally brought it home and connected it through my home network, as I hadn't tried that option in her office due to lack of a patch cable.  Everything worked fine here, and the firmware was updated.  I took it back to her office today, connected it to the router via CAT5e cable, and installed the software on the town supervisor's computer, as she was busy finishing a report.

All the functions from the supervisor's computer worked fine - even the scanning.  After she finished her report, I removed the software from her computer, rebooted, and reinstalled the drivers and utilities.  The installation went fine, except it still will not print (the command cannot be completed).  However, I can scan a document from the MFP and save it on her computer.  What's baffling is that there is also a Canon 8380C in her office, which is on the network, and she can print to that without a hitch.  The HP Scan and Print Doctor goes through its procedure, and still won't print a test page.  For some reason, there's a message about updating the software and drivers, yet the file is exactly the same as the one I'm using.

She has Avast for her security software, and it's configured to "trust" the office network.  Even if I disable the protection, printing still won't work.  I'm at a loss on this one, so I'm hoping someone has a solution.  Could it be an outdated DLL, which I can copy from the supervisor's computer?

Thank you.