wp-login.php error 404

Hi everyone.

For the past week, I have not been able to access my site’s dashboard. While the website’s frontend works perfectly fine, the backend is completely inaccessible via the web interface. I can access it from the WordPress iOS app, but that’s about all I can do.

• I deactivated the plugins using phpMyAdmin, but that didn’t do anything (so I put them back).
• I renamed the plugins folder but that didn’t do much.
• I changed the permissions for the wp-config file from 640 to 644 but that didn’t do much either.

My url is http://ecaconcordia.ca and the backend url is http://ecaconcordia.ca/wp-admin/.

Thank you for your help, I am completely at a loss at this point.

-Chrissar