Unable to establish a network connection to the server.

[Zied90]

a repetitive backup error for a virtual server running Windows Server 2012 R2.

the error message is as follows:

V-79-57344-65064 - Unable to establish a network connection to the server.

Remote Agent not detected on Ip adress .


the problem that I tried all possible solutions such as:

- agent update
- agent re-installation
- connection establishment
- deletion then addition of the remote server in the backup server

(firewall is down on the remote server ) 
sometimes the backup only works for 2, 3 days then the same error

I don't know what to do to solve this problem

[PJ_Backup]

Hi - it might be worth checking the BE Settings to do with network as follows:
Configuration & Settings - Backup Exec Settings - Network and Security - then change 'Network interface' from:
"Use any available network interface" to the specific NIC you want to use - and also change 'Protocol' from:
"Use any available protocol" to IPv4. Finally uncheck 'Allow use of any available net interface, subnet or protocol...etc'

This sometimes has an effect in network communication problems, sometimes no effect, but its worth a try.
I'd also recommend removing the BE Server in the publishing tab on the remote client (vxmon.exe) and adding it back in - though it sounds like you may have tried that anyway.