The IBM command server places messages on this queue which are responses to the requests coming from Navigator components. This can be caused by SYSTEM.ADMIN.COMMAND.QUEUE being defined with DEFPSIST(YES), which causes persistent messages to be created. If you are getting messages on DLQ with with error, RC2048 : MQRC_PERSISTENT_NOT_ALLOWED, verify DEFPSIST and set to NO to not allow the messages to be persistent.