The most recent version of Sage promotes a feature that allows you to backup the database when multiple users have the data open.

Unfortunately the feature doesn’t currently work, as the backup will fail when you try.

There is an easy way to roll back to the old way of manually backing up the database and the instructions are below:

Open Sage, then go to Settings, Company Preferences and the Parameters tab.

There is an option at the bottom called “Enable check data and backup with users logged in”. Un-tick this option to save data the old way (with no other users logged in when saving).