Backup Failure During Verification

Hi,

I am taking backup of one of one REMOTE Server having WINDOWS Storage Server and Backup Agent installed. The backup size is approx 2.5 TB. When i run the full backup of 2.5 TB its run and its taking to much time to verify the same and after that the same fails.

If we split the same backup in two it having the backup size around 1 TB each job completed successful without any errors the same is happened even after installed all the Service packs update on remote and SBE 2012 and service pack 4.

Now again we created one FULL BACKUP from the same copy of old one. Its works fine even after verification. Now my suggestion/question is that why the verify job fails OLD backup.