Error on Event Viewer Backup exec 2010 Event id 570860

Hello folks, 

when i open the event viewer i get the following error, " An error occurred while attempting to log into the following server: "Servername" 

SQL error "0011"

Im not sure what the error is about, since apparently everyhing is working fine, my daily full backups are backing up, my daily database maintenance is working, not other error on event viewer. 

any help would be appreciated thanks