The problem behind this funcationality is that the Enterprise Explorer keeps the UI thread running during server calls (in order to get good responsiveness for the user). However, that makes message that are posted with PostMessage to be executed too early (and commonly, message handlers for posted messages do database calls) The solution is to queue all posted messages and on the Application.Idle event dequeue and send the messages to the correct destinaion. When database calls are being made and Enterprise Explorer keeps the UI running, the dequeueing could temporarily be disabled.