Diagnosis
An error occurred when calculating the selection horizon. (See messagein log.)

System Response
The selection horizon is calculated internally from theplanning horizon and determines the timeuntil which dependent requirements are read and analyzed.
As an error occurred during the calculation, the system only analyzesthe requirements in the planning horizon. Backflushes carried out aheadof schedule for orders planned in the future may not be recognized.

Procedure
Check the control cycle and the scheudling profile.