SAP Message V1526 - Assigned ship-to party &1 is on boycott list for country &2

Diagnosis
The ship-to party you have assigned is on a boycott list.

System Response
In order processing, the order is allowed with a warning. In deliveryprocessing, the delivery is rejected with an error message.

Procedure
Check the ship-to party's foreign trade data in the customermaster and, if necessary, change it.