Unable to establish trust with Backuped hosts.

You could try to regenerate the SSL certificate on the remote server using the following steps:

Stop the Backup Exec remote agent service.

Browse to \Program Files\Symantec\Backup Exec\RAWS\Data directory and rename the existing .cert and .key files

Restart the Backup Exec remote agent service.

Retry to establish a trust from all media servers and see if this works.

Is Backup Exec 2012 and the remote agent up to date ? Do ensure the backup exec remote agent service is running on the remote server and running under a local system account.

Could try few things...

1) Try uninstalling the remote agent and then run a push install from the backup exec server. (push install would automatically establish a trust)

2) Is this remote server part of a different domain or it a DC ? If yes, try this KB - http://www.symantec.com/business/support/index?page=content&id=TECH190536

3) Ensure the system time is in sync between the media server and the remote server

4) Lastly, you could try deleting the certificate files from the remote server and try to re-establish a trust

backup exec 2012 and remote agent is up to date: if i try to backup through other backup exec server(i select in job properties in tab "storage") it work fine.

i try to reinstall agent. it's not work.

It is single domain(but other site), backup exec isn't DC.

system time is sync.

I'd try to reestablish trust and get error in picture above

if i try to backup through other backup exec server(i select in job properties in tab "storage") it work fine

Is this a CASO-MMS setup ?

yes.
Server was installed not by me, but is similar to.

do this on the backed up host?
i do. didn't work.

i guess, that troubles on the backup server. not client side.

It usually is better to do this step on all servers which are being backed up, however in your case, would recommend to do this on the remote server which cannot be backed up.

If the BE server which fails to backup this remote server, also fails to backup other remote servers, then would recommend to regenerate the certificates on that BE media server.