TNS Database Error Messages TNS-12672: Database logon failure December 18, 2020 mpbod TNS-12672: Database logon failure Cause: The authentication service adapter in use encountered an error it attempted to validate the logon attempt of a user. Action: Enable tracing to determine the exact error encountered by the adapter. 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)