TNS Database Error Messages TNS-12168: TNS:Unable to contact Directory Server December 15, 2020 mpbod TNS-12168: TNS:Unable to contact Directory Server Cause: Configured to use LDAP based Directory Server. Action: Bring the Directory Server up or change configuration to LOCAL. 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)