How to cancel update thru an update routine?

Hi

I am using a field routine in the update rule and have to cancel the entire load if a condition is not satisfied and create a monitor entry. I have written the code and when i test it using simulation i get the message "Error 1 in update". what does that mean?

I am pasting the code bit below:

 SELECT SINGLE ...
  IF SY-SUBRC = 0.
     ...
      ABORT = 0.
   else.
* Display error in monitor
     MONITOR-msgid = 'ZBW_TEST'.
     MONITOR-msgty = 'E'.
     MONITOR-msgno = 000.
     MONITOR-msgv1 = COMM_STRUCTURE-SALESORG.
     MONITOR-msgv2 = COMM_STRUCTURE-Plant.
     MONITOR-msgv3 = COMM_STRUCTURE-material.
     append MONITOR.

     ABORT = 8.
     exit.
  ENDIF.

The monitor messaage is also not displayed. What is going wrong here?

Regards

Sujai