When the 767s were very new, there was a known bug in the glass cockpit that could cause all the screens to go blank. I was in an aborted takeoff for exactly that reason. At the time, Boeing hadn't identified the bug, so the work-around was to reboot the cockpit.
But that was back in the mid-1980s. I would think that that bug was long since found and fixed. This is probably something else.
And no, the 767s don't run Windows. Windows didn't even exist back then!