Login Form Hidden on Joomla’s Administrator Login Page

Nearly every day, we have one or two clients calling us and telling us that they can’t login to the backend of their Joomla website. Usually, their problem is one of the following:

• They are seeing a completely blank page when they try to login to their Joomla website. In other words, they see the login form when they go to http://clientjoomlawebsite.com/administrator but when they enter their credentials (and press on the “Log in” button) they see a blank page. Usually, the cause of this problem is a PHP error in one of the non-core system plugins.

• They are seeing a completely blank page instead of the login screen. The root cause of this problem is an error in one (or more) of the core Joomla files that loads the login screen. This is not very common, but it does happen, especially after a PHP and/or a MySQL upgrade for websites that are powered by a modified Joomla core.

• They are seeing an “invalid token” error when they enter their credentials. There are many, many causes to this problem, ranging from issues with cookies to badly written and/or conflicting extensions.

• They are getting a “username and password do not match” error, although they are absolutely sure that they are correct. Again, the causes of this problem are many, ranging from a hacked website (e.g. the Joomla database is hacked and the password of the super admin is altered by the hacker) to a PHP upgrade (by the hosting company) that creates session issues making administrators of some old Joomla websites unable to login.

• They are able to login, but they are not able to see the menu. The cause of this problem (in most cases) is wrong permissions, and it usually happens when the Joomla administrator alters default Joomla’s permissions that have to with viewing access. Fixing the problem can be done by resetting Joomla’s default permissions.

As you can see, we have seen all the Joomla login issues and we have fixed them all – or so we thought!

This time it was different. The Administrator login page was displaying (so it wasn’t blank), but the form was not. Only the sentence:
“Use a valid username and password to gain access to the Administrator Back-end.” along with the standard Joomla “lock” image showed up. Take a look at the below picture to see what we mean:

What could be the cause of the above problem, we wondered?

Our first attempt was to check the index.php file located under the administrator folder to see if it was tampered with. It was OK – we then checked the admin.login.php under the administrator/components/com_login and it was also OK. We then started debugging the admin.login.php file, and we noticed that the line: $module = & JModuleHelper::getModule('mod_login'); is being executed properly, but it’s returning an empty string – which means that the module might’ve been disabled. We then printed, using the below code the module information to see if it was disabled or not (we didn’t have phpMyAdmin access to the database):

	jimport( 'joomla.database.database' );
	$db = JFactory::getDBO();
	$query = "SELECT * FROM #__modules WHERE module='mod_login'";
	$db->setQuery($query);
	$arrResult = $db->loadObjectList();
	$objResult = $arrResult[0];
	print_r($objResult);

and we had the following returned:

stdClass Object
(
	[id] => 2
	[title] => Login
	[content] => 
	[ordering] => 1
	[position] => login
	[checked_out] => 0
	[checked_out_time] => 0000-00-00 00:00:00
	[published] => 1
	[module] => mod_login
	[numnews] => 0
	[access] => 0
	[showtitle] => 1
	[params] => 
	[iscore] => 1
	[client_id] => 1
	[control] => 
)

The returned result demonstrates that the mod_login module has not been disabled (since published is set to 1). We then thought, let’s see if the login module actually exists under the administrator/modules folder, and to our surprise, not only the mod_login folder did not exit, the whole modules directory did not exist. Further investigation concluded that the previous designer working on our client’s Joomla website has deleted the whole administrator/modules directory (possibly to block our client from making edits to the website), so we re-uploaded a clean copy of the modules directory (to the right location), and the problem was fixed (although we have later discovered that the designer has also changed our client’s password, so we reset it).

Now, if you’re having the same problem as above (or any other Joomla login problem, for that matter) and you’re not able to solve it yourself, then fear not, we will help! Just contact us and we’ll fix it for you in no time (usually this only takes a few hours). By the way, you needn’t worry about our fees, they are very competitive!