The RG agent and the Avamar client work as a LOCAL SYSTEM and a network drive is mounted in the user session. To backup a network drive you will need :
1 - Create a local account with password on the windows machine which will be a member of the local group "administrators".
2 - Launch the Avamar customer service with this user account
3 -Create the same account on the NAS (same login and password as on the machine)
4 - On the NAS, this account should have at least read rights on the shares to be backed up.
5 - From the RG dashboard, in the RG Backup config, enter the UNC paths to be backed up.