Hi there, I am trying to see if I can create a SIP NOTIFY message with mesage waiting headers. I am using mod_managed and so far did the following in a little event loop: var mw_event = new FreeSWITCH.Native.Event("MESSAGE_WAITING", string.Empty); if (mw_event != null) { mw_event.AddHeader("MWI-Messages-Waiting", "yes"); mw_event.AddHeader("MWI-Message-Account", "sip:3475559995@64.40.xx.xxx"); mw_event.AddHeader("MWI-Voice-Message", "3/1 (1/1)"); mw_event.AddHeader("Profile", "internal"); mw_event.Fire(); } else { Log.WriteLine(LogLevel.Alert, "Failed to create message waiting event"); } However when at each AddHeader FS complians: "Trying to addHeader an event that does not exist!" mw_event is not null however. Can someone point me the right direction - on to create that event correctly. I tried SWITCH_EVENT_MESSAGE_WAITING and NOTIFYas the event type also. Thanks! Pj