Diagnosis
You have entered in the source list an outline agreement item that hasno material number and belongs to the category standard.
An agreement item without a material number can only be used to procurematerials with a master record if it belongs to one of the categoriesmaterial unknown or material group.
Orderbuch: man versucht einen RV ohne Matnr. und Postyp Normal einzugebe
Kontrakt kann für Abruf nicht verwendet werden; Postyp Normal kann
nicht verwendet werden

Procedure
Check your input. If necessary choose a different outline agreementwithout a material number and with the item category materialunknown or material group.