The following message appears on a regular basis in the dialog journal:
"Error: (execute slot single)50000 0 re-throw in Procedure QBM_ZRecalculate, Line 26?50000 0 detected in (SRV=SRV-379\IAM, DB=D1IM) Procedure QBM_ZRecalculate, Line 15?50000 0 task to recalculate not found: <empty>"
This is a product defect (28948).
This will be fixed on a future release of the product. If you require this immediately corrected, please contact Support for a hotfix referencing the defect ID 28948.