The first line should read

<?php namespace App\Http\Controllers;

and does your Auth controller have the line

use App\Http\Controllers\Controller;

at the top?

Doing an upgrade from 4.2 to 5 and having this issue as well. I've tried jacksoncharles suggestions, but they didn't fix the issue at hand. Anyone have any further advice/suggestions?

Did you update your composer.json to use psr-4 ?

	"psr-4": {
		"App\\": "app/"
	}

Yes. I am using the composer.json from the Laravel 5 install and it includes psr-4.

I am facing similar problem when migrating from Laravel 4.2 to 5 (Laravel 4.2 to 5 Class 'App\Http\Controllers\Controller' not found ). Would appreciate any pointers in this regards.