The most common reason for scheduled backups failing is that the Jim2 Server process does not have security to write to the network directory, or a directory path containing a drive mapping is entered.
Jim2Server will log an explanatory error to the windows application event log when unable to perform a backup.
This event log error should indicate the reason the backup failed. The event log can be viewed using the Windows Event Viewer application, which is accessible within the Administrative Tools folder in the Windows Control Panel.
Example situations where backups can fail
Using a Mapped Drive (eg S:\backups)
If drive S: is mapped to \\server\share for the logged on user, Jim2 Server may not be able to use S:\ in the scheduled backup path as the S: drive mapping may not be available/set up in the Jim2 Server's account security context.
When Using a UNC Path (eg \\server\backups)
When trying to back up to \\server\share, the \\server\share must allow write access to the share for the Local System Account for the machine on which Jim2 Server is running. This can be achieved by allowing Everyone access to the share, or by allowing write permissions to the machine as per the image below:
The above permissions screen is allowing the Users belonging to the domain HAPPEN.
Further Information
Diagnosing Incoming Email Issues
Diagnosing Outgoing Email Issues
Jim2 Server Scheduled Backup Fails