Registration Format for Application Shortcut Menu Extensions

The registration format for application shortcut menu extensions is as follows:

HKLM\SOFTWARE\Microsoft\Shell\Extensions\ContextMenus\Context\Class\CLSID
   @ = "MenuDisplayName"
   DelayLoad = dword:DLoad

Context
The application you want to add the shortcut menu extension to.
Class
The type of object the shortcut menu extension is for.
CLSID
The Class Identifier (CLSID) of your shortcut menu extension component.
MenuDisplayName
A string specifying the shortcut menu item text that appears in the shortcut menu.
Dload
Specifies whether to delay-load the shortcut menu extension. When delay-loaded, the IContextMenu object is neither initialized nor called until the menu item is invoked. Only one shortcut menu extension can be delay-loaded at a time.

To delay-load the shortcut menu extension, include the DelayLoad value name and give it the value DelayLoad=dword:1. If DelayLoad is missing or set to 0, the shell calls IContextMenu::QueryContextMenu during the call to SHLoadContextMenuExtensions and enumerates the shortcut menu items to add.

Additional resources