10000465 
Message
Business partner has open transactions; therefore the bill-to country cannot be changed. Continue?
Diagnosis
In the 
Business Partners 
Business Partner Master Data 
path, you have opened the Business Partner Master Data window. On the Address tab, in the Bill to or Pay
to area, you have attempted to change the Country field of an existing business partner.
Procedure
If the business partner is linked to an open transaction, you cannot change the Country field in the Pay to or Bill to information.