Description
An error occurred during replication synchronization.
When running the Synchronize Changes tool, the Geodatabase 2 parameter may be used to specify a geodata service that contains the replica that is related to the replica specified in Geodatabase 1. This error may be returned if the geodata service or the ArcGIS Server connection file that is used to connect to the site where the specified geodata services are running cannot be found.
Solution
Learn about replica synchronization
Check the ArcGIS Server connection file or geodata service to confirm that it is accessible.