Hi,
I got the same message. I located the Tech doc.
Summary is:
Backup Exec for Windows Servers (BEWS) fails to perform Granular Restore Technology (GRT) backup with an "access denied" error on a system running Symantec AntiVirus 10.1.
Symantec AntiVirus 10.1.x version prior to 10.1.6.6000 causes GRT backups to fail. To solve the issue, update AntiVirus version 10.1.x to 10.1.6.6000 or later.
I already have 10.1.6.6000 but the Validator didn't detect that.