ORA Database Error Messages ORA-00021: session attached to some other process; cannot switch session May 18, 2015 mpbod ORA-00021: session attached to some other process; cannot switch session Cause: The user session is currently used by others. Action: Do not switch to a session attached to some other process. 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)