Diagnosis
The task is either not contained in the currently valid task hierarchyor cannot be executed in the current period. When status management isactive, you can process only those tasks that are assigned to the taskhierarchy and are executable in the current period.

Procedure
Check the task hierarchy in the workbench and assign the task to thetask hierarchy.
Also check the task's consolidation frequency to see if the currentperiod is a valid consolidation period.