Excerpted from the LISTSERV README file you get with the code:
 
   LISTSERV's  A-disk will  contain,  after installation,  a file  called
   LISTSERV FILELIST  which is  of crucial importance  and should  not be
   overwritten. If  the userid  of your  server is  LISTSERV and  you use
   FILELIST rather  than FLIST to view  files, be aware of  the fact that
   the FILELIST command may, in certain cases, gladly overwrite this file
   without  prompting you  for confirmation  nor even  notifying you.  In
   particular, typing SAVE or FILE while within FILELIST is a no-no.
 
You have 3 options:
 
1. Don't use FILELIST.
 
2. Try to convince IBM to fix FILELIST (good luck).
 
3. Make  a FILELIST EXEC on  LISTSERV 191 that  makes a copy of  the file
   before calling IBM's FILELIST if the  file was still intact, or prints
   an error message if it got corrupted.
 
Since I  never use  FILELIST (I can't  stand it), I  wasn't aware  of the
problem until it was too late to change the name.
 
  Eric