Microsoft Hyper-V does not start on an AMD Carrizo-based computer that is running Windows 8.1 or Windows Server 2012 R2

Applies to: Windows Server 2012 R2 DatacenterWindows Server 2012 R2 EssentialsWindows Server 2012 R2 Foundation

Symptoms


When you try to start Microsoft Hyper-V on an AMD Carrizo-based computer that is running Windows 8.1 or Windows Server 2012 R2, Hyper-V does not start. Additionally, you receive an error message that resembles the following:

Virtual machine "VM_name" could not be started because the hypervisor is not running.

Cause


This problem occurs because Hyper-V incorrectly identifies the Carrizo System-on-Chip (SoC) as a legacy AMD K8 processor.

Resolution


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.

Prerequisites

To apply this update in Windows 8.1 or Windows Server 2012 R2, you must first have update 2919355 installed.

Restart requirement

You do not have to restart the computer after you apply this hotfix.

Hotfix replacement information

This hotfix does not replace any previously released hotfix.

Status


Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.

References


Learn about the terminology that Microsoft uses to describe software updates.