An Image backup will fail out for a specific volume repeatedly. This failure will present in the job logs as something similar to:
Failed to back up \\?\Volume{d0783469-d069-11e2-93e8-806e6f6e6963}\.
Failed to back up C_Drive (C:).
This problem may persist if you remake the backup set or reinstall the software. If you look in the Agent.log file corresponding to the failed backup job, you see an error similar to:
System.AggregateException: AggregateException_ctor_DefaultMessage ---> System.InvalidOperationException: Not enough data was available for completing block 429,129,723,904 - 429,129,728,000. Error at offset 429129723904....---> (Inner Exception #0) System.InvalidOperationException: Not enough data was available for completing block 429,129,723,904 - 429,129,728,000. Error at offset 429129723904....---> (Inner Exception #1) System.IO.IOException: The drive cannot find the sector requested.
Explanation
The important part of the above error stack is this part:
---> (Inner Exception #1) System.IO.IOException: The drive cannot find the sector requested.
This indicates an issue with the Backup Agent reading from the source disk, specifically in locating a sector it is attempting to back up. Since the problem lies in reading the source disk, this issue is very rarely fixed by reinstalling the software or redoing the backups.
Resolution
Checking Disk Integrity
The first course of action is to run a chkdsk on the volume failing the Image backup. For this issue, it is strongly recommended you run the chkdsk with the following syntax:
chkdsk x: /r
...where x: is the volume targeted in the command. The reason for using the /rflag instead of the /f one is so the chkdsk routine will scan for and attempt to recover bad sectors on the drive. More information about that is here.
Disk Resizing
This resolution has been seen to be applicable to HP servers but may work for any computer whose volumes are allocated irregularly. The drive cannot find the sector requested error has been observed in Windows Backup jobs of HP servers and appears to stem from HP's Intelligent Provisioning Tool (IP). When first creating a machine, one can use the Intelligent Provisioning Tool to provision the volumes on a system automatically. This seems more likely in versions IP 1.5 and older.
The resolution from the above article is to shrink the volume which fails in the image backup and then reallocate that space manually (using Disk Management or diskpart). Here's an outline of the process:
- Use Windows Backup as a testing vehicle. If you run Windows Backup of the failed volume and if it fails or produces a backup which is smaller than the source volume, this indicates an unfavorable result.
- Shrink the failed volume in Disk Management (you can try shrinking by 1GB (1024MB) to start off with). You should then see unallocated space.
- Try performing another Windows Backup. If it works, continue to (4) but if not, repeat (2).
- Reallocate the space you shaved off the volume and try the Windows Backup again. If it succeeds and is consistent in size, the Image backup should work.