Diagnosis
You should not create vendor master purchasing data for purchasingorganizations if a reference purchasing organization, whose referencerefers to the area vendor master, is assigned to it.
If such a reference purchasing organization is assigned to yourpurchasing organization, then the purchasing data of the referencepurchasing organization is used if you create a purchase order for thepurchasing organization.
As a purchasing organization can be assigned subsequently to areference purchasing organization, you are prevented from changing thevendor master purchasing data for this purchasing organization.