Backup Exec 2010 Hyper-V agent GRT enabled Backup to disk jobs targeted to Advanced Format 4K Sector disk drives complete with exception

Article:TECH162930  |  Created: 2011-06-22  |  Updated: 2014-03-13  |  Article URL
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Technical Solution


When using the Backup Exec 2010 Hyper-V agent to perform a GRT backup to disk job targeted to a large disk (2TB or Greater) the job completes with an exception and GRT selections are not seen in the restore view.   This issue occurs when the backup to disk folder is located on an Advanced Format 4K Sector drive.  Typically these drives are 2TB or greater.  Additionally the issue can occur with NAS devices or storage arrays that format or emulate volumes with 4K sectors.




"V-79-57344-38721 - Failed to mount one or more virtual disk images". "Error mounting disks (0xe0009741)"



In order to perform a GRT backup to disk Backup Exec must be able to mount the VHD files on the Backup Exec media server backup to disk location.  Due to Microsoft limitations Backup Exec is unable mount and access VHD files on Advanced Format 4K Sector drives or volumes. See Additional Microsoft Links below.


BEREMOTE Debug log from Backup Exec Media Server

[mounter]            - MSVS_VDiskMounter::GetParentHelper: cracking open "E:\USB H\IMG000044\D\VHD\TEST_C_DRIVE.vhd"
                      - IVhdFileUtil::load_VHD_structures(): the VHD footer failed checksum verification
[mounter]            - Error mounting disks (0xe0009741)
[fsys\ntfs\img_pdi]  + img_pdi_attach.cpp (477):
[fsys\ntfs\img_pdi]  | changing VM Guest Computer name from 'DCEXT' to 'TEST.TEST1.local' as the 'to' name is what was used to make the NDMP connection.
[fsys\ntfs\img_pdi]  + img_pdi_attach.cpp (551):
[fsys\ntfs\img_pdi]  | Error mounting disk(s): E_IMG_FS_FAILED_TO_MOUNT_VIRTUAL_DISK (0xe0009741).

Using Hyper-V with large sector drives on Windows Server 2008 and Windows
Server 2008 R2

Information about Microsoft support policy for large-sector drives in Windows

Acknowledgement : Microsoft


Workaround:  (Use any of the following)

  1. Perform a Non-GRT backup. 
  2. Perform a remote agent backup of the Virtual machine using the Backup Exec Remote Agent (RAWS).
  3. If possible format the backup to disk drive to 512bytes sector size or 512E (Emulation) if the hardware vendor provides a tools for format or 512 emulation.

Symantec Corporation has acknowledged that the above-mentioned issue is present in the current versions of the products mentioned in this this article. Symantec Corporation is committed to product quality and satisfied customers.

This issue is currently being considered by Symantec Corporation to be addressed in the next major revision of the product.  There are no plans to address this issue by way of a patch or hotfix in the current or previous versions of the software at the present time.  Please note that Symantec Corporation reserves the right to remove any fix from the targeted release if it does not pass quality assurance tests or introduces new risks to overall code stability.  Symantec's plans are subject to change and any action taken by you based on the above information or your reliance upon the above information is made at your own risk.

Please be sure to refer back to this document periodically as any changes to the status of the issue will be reflected here.
Please contact your Symantec Sales representative or the Symantec Sales

Supplemental Materials


Hyper-V: GRT enabled backup to disk of Hyper-v guest OS completes with exception: "V-79-57344-38721 - Failed to mount one or more virtual disk images". "Error mounting disks (0xe0009741)"



Failed to mount one or more virtual disk images

SourceError Code

Error mounting disks

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