You are currently offline, waiting for your internet to reconnect

"0x8007007A" error when you migrate a virtual machine that's running Windows Server 2012 R2 or Windows Server 2012

Consider the following scenario:
  • You have two Hyper-V hosts that are running Windows Server 2012 R2 or Windows Server 2012.
  • You use the Live Migration feature in Hyper-V to migrate a virtual machine from one server to another.

In this scenario, the migration fails. Additionally, a "0x8007007A" error that resembles the following is logged in the System log:

Log Name: System
Source : Microsoft-Windows-Hyper-V-High-Availability
Event ID: 21502
Level : Error
Message :Live migration of 'VM_Name' failed.Virtual machine migration operation for "VM_Name' failed at migration source 'Node_Name'. (Virtual machine ID VM_GUID) Failed to save the virtual machine partition state: The data area passed to a system call was too small. (0x8007007A). (Virtual machine ID VM_GUID)

To resolve this issue in Windows Server 2012 R2, install update 2919355.
To resolve this issue in Windows Server 2012, install the hotfix that is described in this article.

Update information for Windows Server 2012 R2

For more information about how to obtain update 2919355, click the following article number to view the article in the Microsoft Knowledge Base:
2919355 Windows RT 8.1, Windows 8.1, and Windows Server 2012 R2 Update April, 2014

Hotfix information

A supported hotfix is available from Microsoft Support. However, this hotfix is intended to correct only the problem that is described in this article. Apply this hotfix only to systems that are experiencing the problem described in this article. This hotfix might receive additional testing. Therefore, if you are not severely affected by this problem, we recommend that you wait for the next software update that contains this hotfix.

If the hotfix is available for download, there is a "Hotfix download available" section at the top of this Knowledge Base article. If this section does not appear, contact Microsoft Customer Service and Support to obtain the hotfix.

Note If additional issues occur or if any troubleshooting is required, you might have to create a separate service request. The usual support costs will apply to additional support questions and issues that do not qualify for this specific hotfix. For a complete list of Microsoft Customer Service and Support telephone numbers or to create a separate service request, go to the following Microsoft website: Note The "Hotfix download available" form displays the languages for which the hotfix is available. If you do not see your language, it is because a hotfix is not available for that language.


To apply this hotfix, you must be running Windows Server 2012.

Restart requirement

You may have to restart the computer after you apply this hotfix.

Hotfix replacement information

This hotfix does not replace any previously released hotfix.

File information

The English (United States) version of this hotfix installs files that have the attributes that are listed in the following tables. The dates and the times for these files are listed in Coordinated Universal Time (UTC). The dates and the times for these files on your local computer are displayed in your local time together with your current daylight saving time (DST) bias. Additionally, the dates and the times may change when you perform certain operations on the files.

Windows Server 2012 file information and notes

Important Windows 8 and Windows Server 2012 hotfixes are included in the same packages. However, only "Windows 8" is listed on the Hotfix Request page. To request the hotfix package that applies to one or both operating systems, select the hotfix that is listed under "Windows 8" on the page. Always refer to the "Applies To" section in articles to determine the actual operating system that each hotfix applies to.
  • The files that apply to a specific product, milestone (RTM,SPn), and service branch (LDR, GDR) can be identified by examining the file version numbers as shown in the following table.
    VersionProductMilestoneService branch
    6.2.920 0.20 xxxWindows 8 and Windows Server 2012RTMLDR
  • The MANIFEST files (.manifest) and the MUM files (.mum) that are installed for each environment are listed separately in the "Additional file information" section. MUM and MANIFEST files, and the associated security catalog (.cat) files, are extremely important to maintain the state of the updated components. The security catalog files, for which the attributes are not listed, are signed with a Microsoft digital signature.
For all supported x64-based versions of Windows Server 2012
File nameFile versionFile sizeDateTimePlatform
Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.

Additional file information

Additional file information for Windows Server 2012

Additional files for all supported x64-based versions of Windows Server 2012
File nameAmd64_bf139c8c0e5bd294380fd47acabdd031_31bf3856ad364e35_6.2.9200.20866_none_6bd745f38681c2c3.manifest
File versionNot Applicable
File size703
Date (UTC)31-Oct-2013
Time (UTC)07:27
SHA-1 hashNot Applicable
MD5 hashNot Applicable
File nameAmd64_microsoft-hyper-v-vstack-vmwp_31bf3856ad364e35_6.2.9200.20866_none_8eab7a7a02986d9a.manifest
File versionNot Applicable
File size387,262
Date (UTC)31-Oct-2013
Time (UTC)02:34
SHA-1 hashNot Applicable
MD5 hashNot Applicable
See the terminology Microsoft uses to describe software updates for more information.

Article ID: 2905249 - Last Review: 04/08/2014 22:09:00 - Revision: 2.0

Windows Server 2012 R2 Datacenter, Windows Server 2012 R2 Standard, Windows Server 2012 Datacenter, Windows Server 2012 Standard

  • kbautohotfix kbqfe kbhotfixserver kbfix kbexpertiseinter kbsurveynew kbbug KB2905249