Hi, Events are signaled by calling the Invoke method of an IDispatch interface supplied by container. The interface lives in the apartment of its own thread, which is also the one containing the control itself. To comply with the STA model, we can only safely call this interface's methods from the thread in which it was created. If the control wants to signal an event from a different thread it must Marshal the IDispatch interface into the IStream first and then UnMarshal it. And of course it must call CoInitialize() too. To Marshal/UnMarshal interface pointers you can use my favorite functions: CoMarshalInterThreadInterfaceInStream(...) and CoGetInterfaceAndReleaseStream(...). Regards, Alex Gorev, Dundas Software.
