Ahsay is an online backup system which doesn’t use tapes. @VIkasmadan : You shouldn’t answer topics unless you fully understand the issue.
The error means the incremental blogs are out of sync and most probably has happened because a previous backup has failed, VSS has changed during the snapshot and transfer stage, or the internet connection is unreliable.
As a side note, we have seen more of these issues with Exchange or SQL where transaction logs are in use.
How to fix
Check your VSS is healthy by running this command in an elevated CMD window vss list writers
Check all disks have plenty of free space for temp locations.
Check Windows event logs (app and system) for hardware or any other errors.
Run another full backup. This can be done using the ‘advanced’ option when manually submitting a backup.