Hi:

You can find some examples in the standard objects. For instance: duplication is not allowed in purchase invoices (GESPIH). Take a look at the SETBOUT object action in the SUBPIH/SUBPIHA process:

$ACTION
  Case ACTION
    When "SETBOUT" : Gosub SETBOUT
  Endcase
Return

$SETBOUT
  If CLECUR
    Call VIREBOUT(CHAINE,"D") From GOBJET
  Endif
Return

The duplication is enabled by default. So, if you want to forbid the duplication, you have to add the code "Call VIREBOUT(CHAINE,"D") From GOBJET" in the $SETBOUT label.

Thank you so much.

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