I seem to have got myself in a bid of trouble.. I was polishing up some of the folders in the root directory of my mainsite as well as in the database and now the backend is not its not letting me login
On one other browser i am still logged in however i looked in the user manager all the users have gone! i ve tried to add a new Super admin but its not letting me select which Group to assign the user to as Super Admin.. I ve attached a screen shot to describe the user manager option and problem.
How about re-upload the files inside the administrator folder from the fresh joomla installation package? Did you backup your site before you changed anything?