how to add include in MV45AFZZ ??

Hi,

In ECC 6.0, I need to add code in the user exit

FORM USEREXIT_SAVE_DOCUMENT

ENDFORM.

How do I do that ? Should I have to implement the implicit enhancement point present at this spot in the include MV45AFZZ ? Or any other way ?

I just need to add an INCLUDE statement inside this FORM. Can anyone give the exact steps ?

thks