-       ResponsePacket.DisconnectionResponse.DestinationChannel = ChannelData->RemoteNumber;
-       ResponsePacket.DisconnectionResponse.SourceChannel      = ChannelData->LocalNumber;
+       ResponsePacket.DisconnectionResponse.DestinationChannel = (ChannelData != NULL) ? ChannelData->RemoteNumber : 0;
+       ResponsePacket.DisconnectionResponse.SourceChannel      = (ChannelData != NULL) ? ChannelData->LocalNumber  : 0;