Symptoms
Avamar Exchange Backup failing with "avexvss Error <18187>: Backup Agent is not running under the Avamar backup user account".
Backups fail even after the AvamarBackupUser is part of all the required groups.
2019/03/29-08:16:52.16300 [avbackupusercfg.exe] CN=AvamarBackupUser,CN=Users,DC=#######,DC=se
2019/03/29-08:16:52.16300 [avbackupusercfg.exe] Leaving function -createuser::GetSearchStrLDAP
2019/03/29-08:16:52.17899 [avbackupusercfg.exe] User is member of CN=Avamar Roles group
2019/03/29-08:16:52.17899 [avbackupusercfg.exe] User is member of CN=Organization Management group
2019/03/29-08:16:52.17899 [avbackupusercfg.exe] User is member of CN=exchange.trusted subsystem group
2019/03/29-08:16:52.17899 [avbackupusercfg.exe] User is member of CN=exchange.servers group
2019/03/29-08:16:52.17899 [avbackupusercfg.exe] User AvamarBackupUser is NOT a member of Exchange Servers group
Cause
In the above scenario, even if the security group memberships are correctly assigned, the group naming convention is an Exchange Legacy Distinguished Name different from the Default security group names.
Example:
2019/03/29-08:16:52.17899 [avbackupusercfg.exe] User is member of CN=exchange.servers group
2019/03/29-08:16:52.17899 [avbackupusercfg.exe] User AvamarBackupUser is NOT a member of Exchange Servers group
Resolution
Ensure that the required permission/memberships have been provided to the "Avamarbackupuser"
Please refer to the documentation on the
Avamar Plug-in for Exchange VSS product page.
If you have an
Exchange Legacy Distinguished Name for the AvamarBackupUser account.