The integration feature is provided by a DiffMerge-supplied library that is loaded by Windows Explorer. This library must be registered with the operating system before Windows Explorer will use it. This is a system-wide registration and will affect all users of the computer.
Once the library has been registered with the system, you may personally enable or disable the feature in your user account.
The Restore Personal Defaults button restores your personal settings to their original factory settings; it does not affect the system-wide registration of the library.