"QBWC1039: There was a problem adding the application. Unique OwnerID/FileID pair required." This is an error message It occurs When you attempt to reconnect the organization document to an outsider application or to Warehouse Manager utilizing QuickBooks WebConnector. If you are troubling by QBWebConnector Error QBWC1039 then you can visit this article where we have explained all about this error with a solution. In case you still have this error then feel free to contact at (844)-888-4666.