Thanks, Gracie!  
The previous week, the Engineer brought up his problem with Ms. Hollings in the lab, and we were able to help him view his pages/documents on a lab computer. Updating the Reader etc on his own computer is of course a better, more thorough & reliable solution.  BTW there was a bad link in some official email he had been sent, which was simply that, a bad link.  (Which however he was able to correct from knowledge of the project name being abbreviated n the URL, or something like that.)