Oracle Message TNS-00005 - INTCTL: error while sending request to the Navigator

ERRORINTCTL: error while sending request to the Navigator
CAUSEThe Navigator is not responding. Either the Navigator is not running or another process is responding.
ACTIONCheck that the Navigator is running by using the STATUS command of the Interchange Control Utility. Verify that the correct addresses are listed in the TNSNAMES.ORA, TNSNET.ORA, and TNSNAV.ORA configuration files.