Diagnosis
You want to block a material that is already assigned to a module. As aresult of being assigned to a module, the material will be listed insubsequent processing.

System Response
The block is permitted.

Procedure
If the module is not yet listed, you should delete the material inmodule maintenance, and then block the material.
If the module is already listed, you cannot delete the material fromthe module. As a result, the block does not apply for the listing, butfor all subsequent processing functions that are still to be carriedout.