"STOP 0x00000079 mismatched_hal" error message occurs after you install Windows XP on a Windows Server 2003-based computer

When you install Microsoft Windows XP on a computer on which Windows Server 2003 is already installed, you may receive a Stop error message that is similar to the following message when you start Windows Server 2003: In this message, the three parameters describe the build type and the Hardware Abstraction Layer (HAL) mismatch.

The Stop error 0x79 message is described as MISMATCHED_HAL or Mismatched Hardware Abstraction Layer. If the first parameter of the Stop error is 3, the operating system loader (Ntldr) is older than the Windows Server 2003 kernel.

To resolve this issue, replace the Ntldr file with a copy from the newest operating system version. To do so:

1. Start the older Windows operating system (for example, Windows XP) by using the Recovery Console. For additional information about how to install and use the recovery console, click the following article numbers to view the articles in the Microsoft Knowledge Base:
   307654  (http://support.microsoft.com/kb/307654/ ) How to install and use the Recovery Console in Windows XP
   314058  (http://support.microsoft.com/kb/314058/ ) Description of the Windows XP Recovery Console
2. At the Recovery Console prompt, type the number of the older Windows operating system installation, and then press ENTER. For example, type the number that corresponds to the Windows XP installation.
3. Type the Administrator password, and then press ENTER.
4. Type c:, and then press ENTER.
5. Type ren ntldr oldntldr, and then press ENTER.
6. Insert the Windows Server 2003 CD-ROM into the CD-ROM or DVD-ROM drive.
7. Type map, and then press ENTER. Note the drive letter that is assigned to the CD-ROM or DVD-ROM drive that contains the Windows Server 2003 CD-ROM.
8. Type copy drive:\i386\ntldr (where drive is the letter of the CD-ROM or DVD-ROM drive that contains the Windows Server 2003 CD-ROM), and then press ENTER. For example, type copy d:\i386\ntldr, and then press ENTER.
9. Type exit, and then press ENTER to quit the Recovery Console.

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

New Windows operating systems such as Windows Server 2003 support backward compatibility in their operating system loaders. For example, the Ntldr file in Windows Server 2003 supports the loading of previous operating systems such as Windows XP and Microsoft Windows 2000. However, these previous operating systems do not support the loading of Windows Server 2003.

For additional information, click the following article number to view the article in the Microsoft Knowledge Base: