Diagnosis
Promotion modules can only be created if the listing period forthe promotion has been defined, since this period is copiedautomatically into the module as the validity period.Vice versa, you may no longer change the period for thelisting in the promotion header once modules have been createdwith this validity period.
The period in the promotion header results from theearliest and latest listing date at plant group level. After creatinga promotion module, you can still only assign new plant groups with alisting period that is within the period.

System Response
Automatic return to the previous screen.

Procedure
First define all the validity periods and then call thefunction "Create module" again.