Line-by-line tax calculation not active in all company codes.

What causes this issue?

Line-by-line tax calculation is not active in all involved company codes
of this posting.

System Response

The document split behaves differently for documents with active
line-by-line tax calculation than for those without line-by-line tax
calculation. The current posting is cross-company code and includes at
least one company code for which line-by-line tax calculation is not
active. However, to carry out the document split correctly, line-by-line
tax calculation must be activated either for all involved company codes
or for none of the involved company codes of the posting.

How to fix this error?

Check the tax Customizing of all company codes that are involved in this
posting. If the Customizing is correct, you should check why a
cross-company code posting is carried out with company codes of
different tax calculation schemas. This should generally be avoided
because the tax is only ever posted for the leading company code and it
could therefore lead to errors in the tax reporting.
If the tax Customizing and the posting process are correct, use document
summarization to summarize the posting to less than 999 line items. The
document split cannot be carried out for this process.

Procedure for System Administrators

The system issues an error message and will not allow you to continue with this transaction until the error is resolved.

Error message extract from SAP system. Copyright SAP SE.