Restore to Exchange 2010 DAG does not work

Hi

i tried to restore a few mails to a mailbox but this wont work. Backups are all successful without any errors and i can even select single mails on the restore job (GRT activated). But when i start the recovery job following error message occurs:

Error category    : Resource Errors
Error             : e000846a - The resource could not be restored because an error occurred while connecting to the Backup Exec for Windows Servers Remote Agent. 
Make sure that the correct version of the Remote Agent is installed and running on the target computer.

For addi
tional information regarding this error refer to link V-79-57344-33898

we have 2 Exchange Mailbox servers which are in a DAG Cluster (DAGGROUP1). also, we have 2 CAS/HUB servers which are also in a CAS-cluster CASGROUP1). for the loadbalancing we have 2 KEMP loadbalancer (listening to DNS CASGROUP1)

i think the issue is that the needed ports are not forwarded but i cannot find which ports to forward to which server (MBX,CAS)

i am running Symantec Backup Exec 2010 R3 latest PAtchlevel on Microsoft Server 2008 R2

would be great if someone can help me

thanks a lot