TNS Database Error Messages TNS-04006: CMCTL: HOST variable is not defined November 5, 2020 mpbod TNS-04006: CMCTL: HOST variable is not defined Cause: The HOST variable was not set. Action: Set the variable HOST properly and restart the CMCTL program. Back to previous menu https://support.oracle.com/ http://www.oracle.com/ Share this:Click to email a link to a friend (Opens in new window)Click to print (Opens in new window)Click to share on Facebook (Opens in new window)Click to share on LinkedIn (Opens in new window)Click to share on Tumblr (Opens in new window)Click to share on Twitter (Opens in new window)Click to share on Pinterest (Opens in new window)Click to share on Reddit (Opens in new window)Click to share on Pocket (Opens in new window)