From 2003-2011, I worked at an .edu and until 2009 or so, the "student information system" was an old terminal-based ("green screen") application -- written in

From 2003-2011, I worked at an .edu and until 2009 or so, the "student information system" was an old terminal-based ("green screen") application -- written in COBOL and still running on a mainframe. There was a "data warehouse" piece of the overall system and I was often tasked with writing batch jobs to pull various data out of it. The resulting files were in either fixed-width or CSV format and so we "massaged" them a bit before writing them out to .xls files that the end-user could work with. The purpose of most of these was to build a mailing list so that something could be sent out (via snail mail). The criteria were often along the lines of "I need a list of all <PROGRAM> students who haven't registered for the next semester" and such. In each and every resulting data file that was downloaded after the job completed, we had to filter out records for the name "ERROR, ERROR" (last, first). I never found out why but apparently the registrar's office had for years been putting names in as "ERROR, ERROR" when it was illegible/unavailable/whatever. Thousands of these had accumulated over the couple of decades they'd been doing this. (Side note: they really regretted it once a new upgraded system was being set up. They had to manually review each and every one of the "ERROR, ERROR" records.)