2334421 - Warning: Accounting Period is Closing - Financial Closing in Progress for Posting Date

When recording time on a project task you notice a warning message: Accounting period is closing; contact accounting department.

When creating a customer or supplier invoice you notice a similar warning after maintaining the invoice/posting date:

Supplier Invoice: You cannot post the invoice. Financial closing in progress for posting date DD.MM.YYYY.
Customer Invoice: Financial closing is in progress on DD.MM.YYYY. The G/L accountant will check and decide in which period the document will be posted.

It is, however, possible to release the time recording or post the Supplier/ Customer Invoice.

In the General Ledger you verify that the respective accounting period is fully open and that it is still possible to make entries for this period. Why are these warnings generated?

SAP Business ByDesign

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