Hyper-V Backup/Restore QFE Released

If you are backing up your Hyper-V virtual machines using our VSS writer (backing up the physical server) you should be aware of a new Hotfix (KB959962) we released today that addresses three issues. 

Issue 1
If you back up a Hyper-V virtual machine that has multiple volumes, the backup may fail. If you check the VMMS event log after the backup failure occurs, the following event is logged:

Log Name: Microsoft-Windows-Hyper-V-VMMS-Admin
Source: Microsoft-Windows-Hyper-V-VMMS
Event ID: 10104
Level: Error
Failed to revert to VSS snapshot on one or more virtual hard disks of the virtual machine '%1'. (Virtual machine ID %2)

Issue 2
The Microsoft Hyper-V VSS Writer may enter an unstable state if a backup of the Hyper-V virtual machine fails. If you run the vssadmin list writers command, the Microsoft Hyper-V VSS Writer is not listed. To return the Microsoft Hyper-V VSS Writer to a stable state, the Hyper-V Virtual Machine Management service must be restarted.

Issue 3
You cannot restore a Hyper-V virtual machine if the virtual machine was configured to use a legacy network adapter.

You can review the KB article and download the fix at http://support.microsoft.com/default.aspx?scid=kb;EN-US;959962.


Taylor Brown
Hyper-V Integration Test Lead


Comments (2)

  1. Tim Harrington says:

    I only see a hotfix for Vista.  Is there a separate KB for Windows 2008?

    The fix is targeted at “Windows 6.0” which is both Vista and Server 2008 – I have asked to see if we can get that corrected on the site as I agree it’s a bit confusing.


  2. RJY says:

    The hotfix is not working in my env. I have 6 VM’s ( 5 win2k8 and one windows 2003 ). I isolated the problem to a VM with SCSCI disk. If i shutdown that VM, then VSS snapshot is good.

    Failed to revert to VSS snapshot on one or more virtual hard disks of the virtual machine ‘%1’. (Virtual machine ID %2)

    Event ID: 10104


    Thanks for the report I’ll have the test owner for VSS take a look – if you wouldn’t mind can you e-mail me at taylorb – at – microsoft.com (you get the idea)?  That way if he has any further questions or workaround we can get it to you.


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