500 error, when registering account on live site

Hi,

finally made it to the point of getting my site live! thank you laracasts.

A real, bonafide "user" even signed up yesterday. However, after signing up a 500 error is thrown. The user told me they can login fine.

I'm able to SSH into the database, provisioned by Forge, and see the user. I tried it myself and the 500 error seems to be consistent.

How can you find the source of this? My local copy does not yield this result.

Here's the RegisterController.php

class RegisterController extends Controller
{
    /*
    |--------------------------------------------------------------------------
    | Register Controller
    |--------------------------------------------------------------------------
    |
    | This controller handles the registration of new users as well as their
    | validation and creation. By default this controller uses a trait to
    | provide this functionality without requiring any additional code.
    |
    */

    use RegistersUsers;

    /**
     * Where to redirect users after registration.
     *
     * @var string
     */
    protected $redirectTo = '/home';
...

web.php

Route::get('/home', 'HomeController@index')->name('home');

I've double checked the email smtp credentials. at a loss.