You are seeing the below error message when trying to login to the Sync App or in your app's log file.
Sage 50 users
QuickBooks Desktop users
The error typically occurs as a result of the Sync App's reading of the program's SQLite Database.
To clear this error, please do the following:
Open your PC's Task Manager.
Click on the Services tab and locate AutoEntry.DesktopSync.Service.
Right-click on this and click Stop.
Open your PC's File Explorer, paste in C:\ProgramData\DocuRec and hit Enter on your keyboard.
Delete the db.sqlite file located here.
Open the Sync App again, and you should be able to successfully login.