Backup Exec 2012 - problems getting a successful backup

Hi,

We are struggeling getting the backup job ending successful. Attached are the error message.

Are running backup jobs on USB disks that are rotated with 5 different disks. the backup is running but the verifying prosess ends up with failed. Have tried different solutions, such as deleting the catalogs folder, deleting all data on disks for clean start, upgrading the Symantec Backup Exec program with SP2, and several test runs...

Any help will be most appreciated.

Regards,

Geir Tore