Backup Exec 2010 R3 - Enterprise Vault 10 backup issues

Hi,

I need help on Enterprises vault 10 backup is getting fail with Backup Exec 2010 R3,

we are taking weekly full backup for all server, other servers full backups are getting successful but, whenever enterprises vault - full backup is happen, its getting fail as Backup to disk device is offline and because disk folder drive is disconnected from server.

any suggestion to fix this issue.