Solution #00005995
Scope:
All Barracuda Backup Servers, all firmware versions.
Answer:
In some cases the installation process of the Barracuda Backup Agent appears to hung at (+ or -) 98%. What is likely happening is that the Backup Agent is waiting for an API call from the Virtual Disk Service (VDS).
To determine if VDS is running, go to Computer Management > Storage > Disk Management:

If the VDS is running, the page will load as displayed above. If VDS is not running the partitions information will not display. Restarting VDS will allow these partitions to display properly, and fix the issue with the Backup Agent.
Link to This Page:
http://www.barracuda.com/kb?id=50160000000ImbY
http://www.barracuda.com/kb?id=50160000000ImbY