Registry Editor is an advanced tool for viewing and changing settings in your system registry, which contains information about how your computer runs. Windows stores its configuration information in a database (the registry) that is organized in a tree format. Although Registry Editor enables you to inspect and modify the registry, normally you do not need to do so, and making incorrect changes can break your system. An advanced user who is prepared to both edit and restore the registry can safely use Registry Editor for such tasks as eliminating duplicate entries or deleting entries for programs that have been uninstalled or deleted.
Using Registry Editor with Windows XP, 64-Bit Edition
The registry in Windows XP, 64-Bit Edition is divided into 32-bit and 64-bit keys. Many of the 32-bit keys have the same names as their 64-bit counterparts, and vice versa. The default, 64-bit version of Registry Editor that comes with Windows XP, 64-Bit Edition displays only the 64-bit keys.
To view or edit 32-bit keys from the registry of a computer running Windows XP, 64-Bit Edition, you must use the 32-bit version of Registry Editor in the %systemroot%\Syswow64 folder. You must close the 64-bit version of Registry Editor before you can open the 32-bit version, and vice versa. There are no differences in the way you perform tasks between the 32-bit version of Registry Editor and the 64-bit version of Registry Editor.
To open the 32-bit version of Registry Editor, click Start, click Run, type %systemroot%\syswow64\regedit, and click OK.