Some thoughts on this:

(1) Check to make sure your SQL Server credentials are correct
(2) Make sure the agent is installed on the target server
(3) Update your BE server using liveupdate
(4) Update your agent(s) using the bulk update tool or manually
(5) SQL permissions for the account you'e using to connect need to have the appropriate permissions (backup operator should be adequate?)

1) Check that the licence for the SQL agent is properly installed.

2) Check that the BE Remote Agent service is running on the remote server.  If need be, set the recovery of the service to restart.

I am able to backup other SQL database which is questys. the problem is IAM NOT  not able to BACKUP laserfitch.Giving me this error. 

I dont have sql server agent but i do have license? how can i download Agent for BE

 I dont have sql server agent but i do have license? how can i download Agent for BE

The SQL "Agent" is just the serial that you install on the media server to unlock the cabability.  You do need to install the Remote Agent on the remote SQL server machine, which is probably correct since you can backup the other database on the same server

any chance that rights within SQL are different for the two databases?

what kind of diffrence can create this error? I realy  did not get why is doing this.

I back up sql database  manually everyday the i use BE.