If you synchronize your customer DB from AOT to SQL server DB and you should receive the following message: cross-company "union all" query cannot contain both a company specific table and a global table unless the data area field is explicitly selected" when synchronizing view DirPartyView then check out this:
Open the view DirPartyView in AOT and check table properties for all corresponding tables. Have a specific eye on the table property: “Save data per company” if this might have been changed during customization. If that is the case then change it back to its original value and make sure that you do not have duplicate records in tables.