JZ : If the extended withholding tax calculation is active in a company code, then it is not only available in the standard processes mentioned. You can also use it in your own programs. To do so, you have to include function module FKK_WITHH_CONTROL_EVENT_0177 in the given program. The module FKK_WITHH_CONTROL_EVENT_0177, in combination with the Customizing settings mentioned, ensures that the program runs an extended withholding tax calculation and in doing so that it processes event 0177.
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