DIIOP security and access

[Robert Laing <rlaing@xxxxxxxxx>]

   We have a CLP program running on our iSeries that calls a Java program
   that composes and sends emails through our Domino server.  The CLP reads a
   PF that contains the server name and a user name and password for
   authentication to the Domino server.  The contents of the emails are in
   other PF's that are read by the Java program.

   The Java program uses Domino classes to compose the email and DIIOP to
   communicate with the Domino server and send the email.

   This is something that has been working for 5+ years with no interaction
   on anyone's part.  Last week it decided to stop working.  Only message in
   the log file is: "DIIOP: user xxxxxxxx cannot access server", where
   xxxxxxx is the short name of the user defined in the PF.  This has been
   the same user name that has worked for 5+ years and is not an actual
   person who interacts with the Domino server.

   The user certificate will not expire for another 10 years, the user
   internet password works fine.  No upgrades or PTF's were loaded on the
   iSeries or Domino when it stopped working.

   Any suggestions on what else to look at ?  Any suggestions on how to
   increase the logging level for DIIOP ?

   V6R1, latest CUM.  Domino 8.5.1 FP1.

   Thanks in advance,
   Bob Laing