This solution applies to Barracuda Backup Service.
There are three likely causes for "Could not mount share"? or "Could not mount first storage group" errors with your Exchange backups:
- Circular logging is enabled on the message store(s) you're attempting to backup. Circular logging prevents the Backup Agent from being able to successfully backup your Exchange Databases due to the log-file recycling that occurs when this is option is enabled. To remedy this, use the System Manager, navigate to the server in question and expand it, and right click on any applicable storage group. Select Properties, and ensure the Enable circular logging checkbox(es) are unchecked.
- Another backup product (such as NTBackup, Backupexec, etc.) is currently used on your server and is truncating your logs. This prevents the Barracuda Backup Service from being able to properly backup and subsequently replay those logs in the event of a restore being required. Thus, the attempted backup fails. Uninstalling these products or disabling the Exchange backup portion of these products will remedy this problem and allow the Barracuda Backup Service to begin backing up your Exchange databases.
- Ensure communication on port 5120 inbound and outbound is open on the Exchange Server. This is the port the Barracuda Backup Agent uses for communication with your local Barracuda Backup Device.