frankypa’s reference worked for me.
1.) Log in to phpmyadmin, click on the database.
2.) Browse the table “wp_usermeta” (if you have database prefixed, the table name is ‘usermeta’ followed by the prefix).
3.) Look for the ‘wp_user-settings’ from the column ‘meta_key’ (make sure the user_id is correct).
4.) Change the ‘meta_value’ to ‘mfold=0’, save your record, and login again.
When I refreshed my phpmyadmin after making the change, it reverted back to “mfold=f”. I made the change again and refreshed and it stuck. After that I logged out of wp-admin and logged back in and the problem was resolved.
doesn’t work for me either.