DDE channel locked

Error 284

You have attempted to initiate a new DDE conversation or perform a DDE method on a DDE link that another application has not freed.  Try calling the DoEventsNPKPD0 function before setting LinkTopicEVWV3S to Automatic (1) or Manual (2) or before performing a LinkExecute0JJE0GF, LinkPokeH222HJ, LinkRequest3HB029, or LinkSendH24SKI method.