Backup or Backup Copy Job fails with the error: “Retrieved less bytes from the storage  than required”.
The point may or may not actually be present on the repository when you browse the storage itself. However, the key issue is that the point shows up as 0 B / Incomplete under the properties of the backups (navigate to Backup & Replication > Backups > Disk, then right-click and select the properties of the backup in question).
As shown, the Data Size/Backup Size both report 0 bytes of data, and the restore point is flagged as Incomplete. However, as shown below, the restore point file can exist on the storage with a non-zero file size:
In very few situations, the contents of the affected backup file may be partially recoverable. However, this prevents us from continuing the chain with the incomplete restore point.
- Ensure the job is stopped and disabled.
- Manually delete the point in question directly from the Repository using Windows File Explorer. Ensure this is the correct file.
- Rescan the Repository under Backup Infrastructure. (https://helpcenter.veeam.com/backup/vsphere/rescanning_backup_repositories.html)
- Have Veeam forget the missing restore point. (https://helpcenter.veeam.com/backup/vsphere/remove_missing_point.html)
- Re-enable and run the job.
In the event these steps do not resolve the issue, it may be necessary to start with a new active full backup, or in a worst-case scenario, to have Veeam remove the current backups from configuration (not from disk; the chain is likely still viable for restores) and start the chain anew. Support can help you to review any options from this point.