Linux workstation would reboot whenever a secretary would print something to her laser printer.

They changed out cables. Bought another printer. I eventually sent them another workstation. Still happened. Defied logic.

I set the printer up remotely to be wireless. Told them to disconnect the USB cable from the computer. Ran lsusb from the terminal session to make sure that instruction was followed. Sent a print job. Her computer shut off.

I asked her why she didn’t tell me that every damned thing on her desk shut off instead of just the computer. “I assumed you knew”. Told her to unplug the laser printer from the battery backup circuit and into the non-protected circuit, put the new workstation I sent them in a box to send back and to relay, in future, every single thing that happens when there is a problem.