SAP Message C7145 - Dates do not exist in the forecast dates

Diagnosis
You want to carry out WBS scheduling using forecast dates. There is anexternal relationship to activity &v1& in network &v1& whereby theactivity itself is not scheduled. There are no forecast dates for thisactivity.

System Response
Since no forecast dates exist, the system uses the basic dates forscheduling.

Procedure
Schedule the complete project using forecast dates to make sure thatall activities have forecast dates.