How to backup/restore SysVol on a domain controller w Netbackup

How can we backup and restore from the location C:\Windows\SYSVOL on our domain controllers? In the backup policy we have it set to do a full backup and if you browse the directory structure it shows all the contents of this folder. However, when you try to run a restore from the server it shows this folder as being empty. We have the Netbackup Client Service running on those servers as a local domain admin account. Those servers also have "Netbackup Legacy Client Service" (not sure what the difference is) which is also running with a local domain admin account. I have also tried enabling Granular Recovery and Cross mount points on the backup policy, but still having the same issue. Our Netbackup admin console is ver 8.1.2