Synchronization needed is an error which can occur when a synchronization has failed for several days and Shoppa was unable to continue. Perform these actions to resolve the issue:
Close every active Shoppa client
Restart the client
If the problem still occurs, delete the database. Learn how to perform a database reset in via the following link: reset your local database
If the problem still occurs it could be related to network issues. Please contact your IT support for help.