Backup Exec 2010 and Exchange Database

Hello, 

I'm receiving errors when i want to launch a backup job for my Exchange server Mailbox Database. I have two clustered (DAG) servers named EX1 and EX2.

The errors is:

After googling i found a solution telling that i've to install a backup exec 2010 R3 Hotfix 180429. But nothing is changed!!

Please somebody help me.