There is a difference between "AboutController@index" and "Controller@index" Make sure you have "AboutController.php" file available in App\Http\Controllers"

Since you are a newbie. Try to first learn about routes in laravel. Its a vast subject, but necessary to learn for use.

Routes : http://laravel.com/docs/5.0/routing Controllers : http://laravel.com/docs/5.0/controllers

I have controller called AboutController in App\Http\Controllers, with function index, I am trying to say that in Main Directory - "http://127.0.0.1" everything loads perfectrly but when try to access a sub directory "http://127.0.0.1/about"(and yes i have it registered in routes) i get 404 error

post your routes.php and AboutController.php

Make sure the AboutController class extends the Controller class

try changing

Route::get('/about', 'AboutController@index');

to

Route::get('about', 'AboutController@index');

you could also list routes (php artisan route:list) (or routes:list) - i always forget if its plural or singular. and see if you route is there.

you could also do php artisan route:cache & then route:clear (it worked for me as i had similar problem) (i say clear the cache otherwise you will have to keep on running cache command everytime you add a new route)