What to do when an error about hardware-assisted virtualization occurs when using Windows XP mode?

You may receive one of the following errors when trying to install, use or configure Windows XP Mode in Windows Virtual PC on a computer running the Windows 7 operating system. These errors may occur if the processor (CPU) in your computer does not support hardware-assisted virtualization (HAV), such as Intel Virtualization Technology (Intel VT), or this feature is not turned on.

NOTE: More information about this issue is available in Microsoft KB Article ID 977206. 

- Unable to start Windows Virtual PC because hardware-assisted virtualization is disabled
- Cannot start Windows Virtual PC Host Process. Check the System event Log for more details
- Windows Virtual PC cannot start because this computer does not support hardware-assisted virtualization 
     

To resolve the errors, first determine if the CPU in your computer supports Intel VT and then use one of the resolutions below:

IMPORTANT: If your computer supports Intel VT, but the setting in the BIOS is not showing, a BIOS update may be available to display this setting. Updates are available online through the downloads section of the support website.

- If the CPU supports Intel VT, enable it in the BIOS.

- If the CPU does not support Intel VT or a BIOS update is not available that allows you to turn on Intel VT, download and install one of the following Microsoft updates to remove the Intel VT prerequisite:

    - For the Windows 7 64-bit operating system use the Update for Windows 7 for x64-based Systems (KB977206).
    - For the Windows 7 32-bit operating system use the Update for Windows 7 (KB977206).