CAUSE&
You want to backward schedule a WBS element, although a basic finishdate has not been entered in either the projection definition, WBSelement or network header for the relevant activities.
Network scheduling:
You want to network schedule a WBS element backward, although a basicfinish date has not been enterd in the corresponding network headers.

System Response
The WBS element is not scheduled.

Procedure
Enter a basic finish date in at least one of the objects mentionedabove.
Network scheduling:
Enter a basic finish date in at least one network header.