I managed successfully to add a button to the conversation window in communicator's GUI using the registry hacks explained in http://technet.microsoft.com/en-us/library/bb963931.aspx. When the button is pressed my application is opened and I can create an object by calling the CommunicatorAPI.Messenger() constructor which I can then use to get a list to all the contacts in my roster, so far so good.
What I would like to do is to gain access to the IMessengerConversationWnd of the conversation window where the button was clicked so that I can then send a custom invite message to all participants.
How do I get access to the relevant object without having a background application running that is registered on the OnIMWindowCreated event?
Thanks,
Simon