Bingo!! Yes, the course in which the error was occurring had a copy of PGML.pl in its macros folder. I renamed it to PGML.pl.old and the pg file then ran successfully with no warnings. There was one other course I checked in which the error occurred, and that course also had a PGML.pl file in its macros folder. I have no recollection of why these two courses had this local copy, but at least none of our other courses had one. So thanks, Alex, for providing the solution. Much appreciated. And thank you Danny, Glen, and Sean for also taking a look at this for me. This forum has come to my rescue many times.
WeBWorK Problems
Error using PGML macro
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