Error Message

 V-79-57344-33932 - Unable to attach to a resource.  Make sure that all selected resources exist and are online, and then try again.  If the server or resource no longer exists, remove it from the selection list. Edit the selection list properties, click the View Selection Details tab, and then remove the resource.

 Job would fail with the error if there are more than one snapshot providers installed on the database server.

Confirm if there are more than one VSS providers installed on the database server and then edit the backup job AOFO settings as below:

a) Open command prompt ( in elevated mode)

b) Run VSSadmin list Providers and check the output 

c) If there are more than one providers listed in the console, go to the Properties of the database backup job in Backup Exec console.

d) Click on Advance open file. 

e) Select the option use Advance open file option and select  Microsoft volume shadow copy provider .

f) From the snapshot provider list select System-Microsoft software shadow copy provider. 

Retry with the job.