Need Help Creating Registration/Login Form

index_page is your the name of your index file (default is index.php), but can be empty if you configured "url rewrite". This never changes once you started using the framework.

What goes after index.php is usually the page that is being requested in the format /index.php/CONTROLLER_NAME/METHOD_NAME/
In your case you have "User" controller and "register" method (or at least you are trying to request/redirect to). Read more here: http://www.codeigniter.com/user_guide/ge...uting.html

Thank you for clearing that up. That was bothering me a lot! It makes sense now. 

Also, thanks to your explanation, I figured out the problem. It was trying to access the "User" controller, but the controller was incorrectly named. So, of course, it wasn't detected when I submitted the form. What a silly mistake.