%MAILSERV-W-
 ALREADYSUB, address is already subscribed to the mailing list

      You are already subscribed to the mailing list. If you used
      the optional address parameter, then the specified address is
      already subscribed. Check to make sure that you specified the
      correct mailing list name or address or both.

  %MAILSERV-W-CANTDELETE, cannot delete old mailing list file

      An error occurred while trying to delete the old mailing list
      file. Try again later; the postmaster in charge of the mail
      server has been notified.

  %MAILSERV-W-CANTUPDATE, cannot update mailing list file

      An error occurred while trying to update the mailing list. Try
      again later; the postmaster in charge of the mail server has
      been notified.

  %MAILSERV-W-ILLADDRESS, illegal address

      You specified an illegal or invalid address for the optional
      address parameter. Resend the command either omitting the
      address entirely or specifying a valid address.

  %MAILSERV-W-INSFPRM, missing command parameters

      You failed to supply the name of the mailing list to subscribe
      to. Resend the command with a list name specification.

  %MAILSERV-W-LNF, list not found

      The mailing list you specified does not exist. Resend the
      command specifying the name of a valid mailing list. You can
      use the DIRECTORY/LIST command to obtain a listing of the valid
      mailing list names.

  %MAILSERV-W-LSTCREERR, unable to create new mailing list

      The mailing list specified by the list-name parameter does not
      exist and could not be created. Check to make sure that you
      specified the correct list name.

  %MAILSERV-W-LSTLOCKED, mailing list currently locked by another user

      The mailing list is currently locked; you cannot subscribe to
      it at this time. Try resending the command again later.

  %MAILSERV-F-NOMAILLIST, mailing lists are not enabled

      The mail server is not configured to operate as a list server.

  %MAILSERV-W-PRV, insufficient privilege or file protection violation

      You are not allowed to subscribe to this mailing list.