Can't log in Joomla Admin Section after Hot Start

I just purchased, downloaded, and installed your Sportal Joomla template. I did the Hot Start Installation in order to have the starting content. The frontend of the site loads perfectly! However, when I go to the backend (administration section), and try to login as admin, I get a "500 - An error has occurred. Return to Control Panel" error message within Joomla. Same goes for when I just to log into the site as the admin from the frontend of the site. In this case, it stops at this URL: http://www..com/index.php/login?task=user.login

I notice one thing. When I go to configuration.php and set SEF = 0, I'm able to see the error message when I try to log in from the frontend of the site. The error message says: " Invalid controller: name='user', format='' "

Please help.

Did you install some additional component/module/plugin after installing it?
Did you ever entered administration?

No...I never entered the admin section, or did anything from the start. I've tried 3 fresh, clean, installs...and get the same error in every case.


Please help.

What about the database , do you create new one or you do installation in existing DB?

I provide the database information (user name, password, database name) during the installation steps, and the installation creates all the Joomla tables in the database. I do not use an previously created or existing set of Joomla database tables.

What version of Joomla have you tested the Hot Start installation with? Currently, the hot installation comes with Jooomla 1.7.2. Have you tested the Hot Start installation with 1.7.2?

Just tested fresh downloaded version, it's ok. Do you have that site online if yes can you give us link, also before that open configuration.php and change:

public $debug = '0';
public $debug_lang = '0';

to

public $debug = '1';
public $debug_lang = '1';