I think that this question already questioned, and probably the answer is here: http://wiki.developers.facebook.com/index.php/Notifications.send but the real problem is that facebook says: Facebook discontinued support for this method March 1, 2010. Calling this method returns error code 3 -- Unknown method. while, I couldn't find any other JS-api for the invitation, anyone know how we can invite users, using the JS api or the .net api? thanks.