By default, a 32-bit application running on WOW64 accesses the 32-bit registry view and a 64-bit application accesses the 64-bit registry view. The following flags enable 32-bit applications to access redirected keys in the 64-bit registry view and 64-bit applications to access redirected keys in the 32-bit registry view. These flags have no effect on shared registry keys. For more information, seeRegistry Keys Affected by WOW64.

These flags can be specified in thesamDesired parameter of the following registry functions:

• RegCreateKeyEx
• RegDeleteKeyEx
• RegOpenKeyEx

Either KEY_WOW64_32KEY or KEY_WOW64_64KEY can be specified. If both flags are specified, the function fails with ERROR_INVALID_PARAMETER.

Windows Server 2008, Windows Vista, Windows Server 2003 and Windows XP: If both flags are specified, the function s behavior is undefined.

TheRegDeleteKey function cannot be used to access an alternate registry view.

The following are best practices when accessing the registry from an application:

• After the application has accessed an alternate registry view using one of the flags, all subsequent operations (create, delete, or open) on child registry keys must explicitly use the same flag. Otherwise, there can be unexpected behavior.
• To accurately enumerate all keys in both views, perform the enumeration in two passes. The first pass should use a handle opened with one of the flags, and the other pass should use a handle opened with the other flag.

For information about accessing the alternate registry view through WMI, seeRequesting WMI Data on a 64-bit Platform.

Related topics

Registry Redirector

Registry Reflection