Diagnosis
You want to change or display the BOM for the WBS element or materialV1. however, you have selected a valid-from date on which the bom isinvalid.

System Response
You can neither display nor change the BOM.

Procedure
Find out about the BOM's validity. You can display time-relatedvalidity as follows:
Choose WBS BOM -> Display.
Delete all the values from the validity data block.
Choose Header.
If the BOM has already been changed with reference to a change number,an overview of all its change statuses with their respective validityappears.
If the BOM has not previously been changed with reference to a changenumber, the Header: Quantities / Long Text screen appears.