Getting a 500 Internal Server Error (require() failed opening required path) on Laravel 5+ Ubuntu 14.04

I have installed Laravel many times on Windows OS but never had this problem. However, on Ubuntu 14.04 I am getting a 500 Internal Server Error, and messages like this in my logs: > [Wed Jul 22 10:20:19.569063 2015] [:error] [pid 1376] [client 127.0.0.1:52636] PHP Fatal error: require(): Failed opening required '/var/www/html/laravel_blog/../bootstrap/autoload.php' (include_path='.:/usr/share/php:/usr/share/pear') in /var/www/html/laravel_blog/index.php on line 22 Previously I've had problems when mod_rewrite was not installed or set up properly, but I have installed it and it is not working. Changed .htaccess as well from original to this. +FollowSymLinks RewriteEngine On RewriteCond %{REQUEST_FILENAME} !-d RewriteCond %{REQUEST_FILENAME} !-f RewriteRule ^ index.php [L] I've given access to all my folders and files inside i.e. > /var/www/html/laravel_project I have all the necessary extensions needed for Laravel 5+ as well. Is there something left that I didn't do?