Add-ins for Office programs may be registered under the \Wow6432Node

Original KB number:   2778964

Summary

If you have a 32-bit version of Office installed on a 64-bit version of Windows, add-ins that are registered under HKEY_LOCAL_MACHINE will be registered under the \Wow6432Node subkey. For example:

HKEY_LOCAL_MACHINE\software\Wow6432Node\microsoft\office\Outlook\Addins

This is important to remember if you are troubleshooting problems in your Office programs and you need to disable add-ins. If you are not modifying the correct registry data (because you do not realize you are running 32-bit Office on a 64-bit version of Windows), then your changes will not change the add-in behavior.

More information

COM add-ins register themselves in the Windows Registry under either the HKEY_CURRENT_USER or HKEY_LOCAL_MACHINE hives. But, if you are using a 64-bit version of Windows, the subkey under HKEY_LOCAL_MACHINE will vary depending on the bitness of your Office installation. See the following table for the correct registry location for the different combinations of 32-bit/64-bit versions of Office and Windows.

Window bitness Office bitness COM add-in registry location under HKEY_LOCAL_MACHINE
32-bit 32-bit HKEY_LOCAL_MACHINE\Software\Microsoft\Office\<application>\Addins
64-bit 64-bit HKEY_LOCAL_MACHINE\Software\Microsoft\Office\<application>\Addins
64-bit 32-bit HKEY_LOCAL_MACHINE\Software\Wow6432Node\Microsoft\Office\<application>\Addins
32-bit 64-bit It is not possible to install a 64-bit version of Office on a 32-bit version of Windows

Note

If you have a 64-bit version of Windows, add-ins that register themselves under HKEY_CURRENT_USER are not affected by this nuance.

Use the following steps to determine the bitness of Windows you are using.

  • Windows 7
    1. Select Start, right-click Computer and then select Properties.
    2. Note the bitness of Windows next to System type under System.
  • Windows 8
    1. Press Window+X.
    2. Select System.
    3. Note the bitness of Windows next to System type under System.

Use the following steps to determine the bitness of Office you are using.

  • Office 2010

    1. Start an Office program.
    2. On the File tab, select Help.
    3. Note the bitness next to the version number in the right-side of the Help section.
  • Office 2013

    1. Start an Office program.
    2. On the File tab, select Account (select Office Account in Outlook).
    3. In the right-pane, select About <program>.
    4. Note the bitness next to the version number in the About <program> dialog box.