ISSUE
Command Failed: Verifying SharePoint User Credentials
----- Client Messages -----
BP Agent service account does not have full permission to backup or restore sharepoint farm. Please set sharepoint farm credentials by using Unitrends Administrator Interface (RRC).See the following Knowledge Base article for additional requirements: http://support.unitrends.com/ikm/questions.php?questionid=851
Farm backup user account: NT AUTHORITY\SYSTEM. BP Agent service account: LocalSystem.
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RESOLUTION
-Go to the Configure tab on the left
-Go to Protected Assets at the top tab
-Find the asset where the Sharepoint Farm is located
-Click the plus sign to "drill down" on the asset and check the Sharepoint Farm instance
-Click edit at the top
-Check the credentials option
-The credentials you use here must be local credentials that have admin rights (you may find previously configured credentials by clicking the ? by Manage Credentials or you may have to add the local credentials with admin rights).
Then try a backup.