Table &1: Withholding tax type &2 in country &3 uses accumulation

What causes this issue?

You have made system settings such that withholding tax type &V2& uses
accumulation in country &V3& (extended withholding tax ). In classic
withholding tax however, accumulation is not possible.

System Response

After the changeover to extended withholding tax, the system would try
to calculate the withholding tax base amount and the withholding tax
amount using accumulation. Since this was not possible in classic
withholding tax, documents would be treated differently before and
after the withholding tax changeover. In particular, note that afte the
changeover, there are no accumulated values for documents posted before
the changeover.

How to fix this error?

Check the following system settings and adjust them if necessary:
Customizing for extended withholding tax: Definition of withholding tax
types: Type of accumulation
Assignment of withholding tax types/codes (second step in conversion
run)

Error message extract from SAP system. Copyright SAP SE.