You receive a "0x00000079 (0x00000004, 0x0000AC31, 0x00000000, 0x00000000)" stop error message when you start a Windows XP-based or a Windows 2000-based guest PC in Virtual PC 2004 (833143)

SYMPTOMS

When you start a Microsoft Windows XP-based or a Microsoft Windows 2000-based virtual machine, you may receive the following Stop error message:

0x00000079 (0x00000004, 0x0000AC31, 0x00000000, 0x00000000)

CAUSE

This issue occurs only if the following conditions are true:

You create a virtual machine with Advanced Configuration Power Interface (ACPI) enabled, and you install Microsoft Windows XP or Microsoft Windows 2000 as the guest operating system.
You create a second virtual machine that does not have ACPI enabled and attach the virtual hard disk image from the first virtual machine as the primary hard disk for the second virtual machine.
The second virtual machine uses the guest operating system on the virtual hard disk image to start up.

RESOLUTION

To resolve this issue, manually turn on ACPI in the BIOS of the virtual machine. If you do not want to use ACPI power management features with your virtual machine, turn off ACPI in the BIOS of the virtual machine (if ACPI is enabled), and then run Windows Setup to install the operating system on the virtual machine.

Note By default, when you create a new virtual machine in Microsoft Virtual PC 2004, ACPI is enabled in the BIOS. You must manually turn off ACPI in the BIOS if you do not want to use ACPI power management features.

MORE INFORMATION

This issue may occur if you install either Windows XP or Windows 2000 on a virtual machine where ACPI is enabled, and then start the operating system on the same virtual machine or on a different virtual machine where ACPI is disabled.

This issue does not occur if you install either Windows XP or Windows 2000 to a virtual machine where ACPI is disabled, and then start the operating system on the same virtual machine or on a different virtual machine where ACPI is enabled. In this situation, the operating system starts as expected. However, ACPI power management features are not available for use with the operating system.