Error message when 64-bit versions of ADPREP fail to execute when they run on 32-bit versions of Windows: “ADPREP.EXE is valid, but is for a machine time other than the current machine”


You try to run ADPREP.EXE from the Windows Server 2003 R2 x64 installation media, but this is unsuccessful, and you receive one of the following error messages:

Error message 1
ADPREP.EXE is valid, but is for a machine type other than the current machine

Error message 2
ADPREP.EXE is not a valid win32 application


The problem occurs when you try to run a 64-bit version of ADPREP from the x64 Windows Server installation media on a computer that is running a 32-bit or x86 version of the Windows operating system.

The problem can occur for either of the following reasons:
  • The administrator did not run a version of ADPREP that was compatible with the processor architecture (x86 or x64) of the Windows operating system that owned the schema or the infrastructure FSMO roles

  • The Windows Server installation media did not include a version of ADPREP that was compatible with the processor architecture of the current and potential FSMO role holders. You frequently encounter this error when you try to add 64-bit Windows Server 2003 R2 domain controllers to existing Microsoft Windows 2000 or Windows Server 2003 R2 domains. This is because the Windows Server 2003 R2 x64 installation media only includes a 64-bit version of ADPREP, and this version is incompatible with the x86 FSMOs that exist in many Active Directory forests.


The hotfix for KB919151 includes the x86-, x64-, and IA-64-compatible versions of ADPREP together with the supporting Sch*.ldf files for the Windows Server 2003 R2 operating system. Run the version of ADPREP that is included with KB919151 and that is compatible with the processor architecture of the current FSMO role holders in your Active Directory forest.

Hotfix information

A supported hotfix is available from Microsoft. 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 this specific problem. 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, visit the following Microsoft Web site: 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.


No prerequisites are required.

Restart requirement

You must restart the computer after you apply this hotfix.

Hotfix replacement information

This hotfix does not replace any other hotfixes.

File information

The English version of this hotfix has the file attributes (or later file attributes) that are listed in the following table. The dates and times for these files are listed in Coordinated Universal Time (UTC). When you view the file information, it is converted to local time. To find the difference between UTC and local time, use the Time Zone tab in the Date and Time item in Control Panel.
File nameFile versionFile sizeDateTimePlatform
409.csvNot applicable78,10002-Jun-200611:10Not applicable
Dcpromo.csvNot applicable1,773,68802-Jun-200611:10Not applicable
Sch14.ldfNot applicable52,19002-Jun-200611:10Not applicable
Sch15.ldfNot applicable27,93902-Jun-200611:10Not applicable
Sch16.ldfNot applicable10,07202-Jun-200611:10Not applicable
Sch17.ldfNot applicable5,71502-Jun-200611:10Not applicable
Sch18.ldfNot applicable15,78902-Jun-200611:10Not applicable
Sch19.ldfNot applicable4,74402-Jun-200611:10Not applicable
Sch20.ldfNot applicable5,65802-Jun-200611:10Not applicable
Sch21.ldfNot applicable3,65002-Jun-200611:10Not applicable
Sch22.ldfNot applicable7,77602-Jun-200611:10Not applicable
Sch23.ldfNot applicable1,88402-Jun-200611:10Not applicable
Sch24.ldfNot applicable3,45602-Jun-200611:10Not applicable
Sch25.ldfNot applicable26,84202-Jun-200611:10Not applicable
Sch26.ldfNot applicable7,70102-Jun-200611:10Not applicable
Sch27.ldfNot applicable28,18602-Jun-200611:10Not applicable
Sch28.ldfNot applicable1,71102-Jun-200611:10Not applicable
Sch29.ldfNot applicable1,45602-Jun-200611:10Not applicable
Sch30.ldfNot applicable7,05402-Jun-200611:10Not applicable
Sch31.ldfNot applicable70,66102-Jun-200611:10Not applicable
Schema.iniNot applicable179,44002-Jun-200611:10Not applicable


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

More Information

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

824684 Description of the standard terminology that is used to describe Microsoft software updates


Αναγνωριστικό άρθρου: 919151 - Τελευταία αναθεώρηση: 9 Οκτ 2011 - Αναθεώρηση: 1