In Reply To:
DBD::mysql::st execute failed: Unknown column 'email_users.user' in 'on clause' at /email/admin/GT/SQL/Driver/MYSQL.pm line 117.
It looks like your database is still at <2.0.6 as the user column in the user table has been changed to 'email' in 2.0.6. You really need to complete the upgrade before you try doing anything else.
Adrian