REPORT ZPOPUP .
**********************************************************
* This program sends a message in a popup window to the
* screens of the logged on users. This method is better,
* then the SAP system message function, because the popup
* window appears immediately (no dialog step is required),
* and better, then the express mail method (the user can
* not avoid it, no dialog step)
**********************************************************
DATA: MESSAGE(128) VALUE 'Test message'.
DATA: OPCODE TYPE X VALUE 2.
DATA: BEGIN OF USR_TABL OCCURS 10.
        INCLUDE STRUCTURE UINFO.
DATA: END OF USR_TABL.

CALL 'ThUsrInfo' ID 'OPCODE' FIELD OPCODE
    ID 'TAB' FIELD USR_TABL-*SYS*.
LOOP AT USR_TABL.
  CALL FUNCTION 'TH_POPUP'
       EXPORTING
            CLIENT         = SY-MANDT
            USER           = USR_TABL-BNAME
            MESSAGE        = MESSAGE
       EXCEPTIONS
            USER_NOT_FOUND = 1.
ENDLOOP.