Why do I get a 404 error when logging into the Joomla admin panel (no matter what data I enter)?

Question

CMS

The panel itself first opens ( mysite.com/administrator/index.php), and then when entering data (any) or simply pressing Enter, it throws a 404 error with the address http S ://mysite.com/administrator/index.php
Tell me what could be the problem? Already searched the entire Internet.
In the config file, the livesite parameter is empty.
Hosting - hosting.reg.ru

Answer 1

/configuration.php:
public $force_ssl = '0';

Answer 2

You know, I just remembered something else.
Some time ago, a serious vulnerability was found in the Joomla admin panel and many hosters forcibly protected the admin panel (someone showed off: they changed the folder, closed it with additional authorization, changed the port). And as one of the options, they forcibly redirected the admin panel to SSL. Perhaps you have the same situation. Try writing to support (I didn't find anything about this in your hoster's FAQ).
Here is an excerpt from my hoster's email:

Dear Clients.
Due to a massive attack on sites running WordPress and Joomla CMS in order to select an administrative password and create a significant load on the servers, we blocked access to the following URIs at the network level:
wp-login.php
and
/administrator/index.php
This does not affect on site functionality. To work in the admin panel, you can access the site using the https protocol (if it is configured, if not, it can be easily configured in the ispmanager panel), or, if you configured sites using the ispmanager panel, on port 8080 (in some cases, it is possible , 81).
We also strongly recommend changing passwords in the admin area for your sites.
This setting does not affect the operation of the VPS in any way, no changes were made inside the containers. Filtering is performed at the network level and affects only the tcp/http protocol.

Answer 3

1. Create one empty material. It is possible without text, for now, later we will go there. let's write something. The material, who does not know, is created in the Joomla admin panel. But I will not describe in detail where it is, because it makes no sense, it seems to me that the person who makes the site on joomla already knows where the materials are created. (assign a url, for example, 404error.html, so that this material opens at the link: www.yourdomain.com/404error.html)
2. Go to the root of the site (you can use Ftp) and copy the error.php file to your template. Error.php is located at: templates/system / Your template is located at: templates/your_template_name / If there is no already existing file error.php at the address of your template, create a new one and copy the contents of the standard file into it.
3. In the new file, change all the code to the one below. Replacing the reference to the material:
*/
// no direct access
defined( '_JEXEC' ) or die( 'Restricted access' );
if (($this->error->code) == '404') {
header('Location: url of your 404 error page');
exit;
}
?>
This redirects the error to a specific file. At the same time, your site does not change, the markup and usability do not change, you can also give a link to the site map in a 404 error. In general, especially for these cases, I made a selection of original 404 error pages. For inspiration, I think.
4. Close the 404 error page from indexing in robot.txt or in the article settings.
Disallow: /404.
That's all.
Copied from the site: andrew-e.com