Try checking the session.php
file in the config folder. Maybe the path of your laravel installation is incorrect.
Also try to check if your application has write access to the session directory.
chmod 777 ./storage/framework/sessions
The CSRF token works by flashing the value to your session, then comparing the value with what was submitted with your form on the next request. If your sessions are not being set then this will always fail.
note: Just clearing the browser cookies works as well sometimes ;)
If you're using AJAX POST dont forget to add the following
in your head section:
< meta name="csrf-token" content="{{ csrf_token() }}" />
in your javascript section:
$.ajaxSetup({
headers: {
'X-CSRF-TOKEN': $('meta[name="csrf-token"]').attr('content')
}
});