Isilon backup from snapshot failed with the Snapshot cannot be mounted error.

Explanation:

The required privileges are not assigned to the domain user for the SMB share backup.

Workaround:

To add privileges to the user:

Log on to the Windows host.
To open the local security policy settings, click Start, and enter: secpol.msc.
Add the service account (domain\username) to the following:
- Act as part of the operating system
- Adjust memory quotas for a process
- Replace a process level token
Add the service account (domain\username) to the local administrators group.
Restart the NetBackup Legacy Network Service.