类'；用户'；新安装后未发现laravel 5.2

我刚刚按照文档中的指南安装了新的laravel 5.2应用程序-https://laravel.com/docs/5.2#installing-拉拉维尔。

这不是我第一次这么做，但我以前并没有遇到过这样的问题。我得到这个错误：

routes.php第15行中的致命ThrowableError：致命错误：未找到类"用户"

我的routes.php我只有：

Route::get('/', function () {
return view('welcome'); });

我不明白问题出在哪里。我在新安装时遇到过这个错误，以前从未遇到过这样的问题。如有任何帮助，我们将不胜感激。

这是一个错误的完整屏幕截图：错误的屏幕截图

错误列表：

FatalThrowableError in routes.php line 15:
Fatal error: Class 'User' not found
in routes.php line 15
at RouteServiceProvider->{closure}()
at call_user_func_array(object(Closure), array()) in Route.php line 158
at Route->runCallable(object(Request)) in Route.php line 137
at Route->run(object(Request)) in Router.php line 724
at Router->Illuminate'Routing'{closure}(object(Request))
at call_user_func(object(Closure), object(Request)) in Pipeline.php line 52
at Pipeline->Illuminate'Routing'{closure}(object(Request))
at call_user_func(object(Closure), object(Request)) in Pipeline.php line 102
at Pipeline->then(object(Closure)) in Router.php line 726
at Router->runRouteWithinStack(object(Route), object(Request)) in Router.php line 699
at Router->dispatchToRoute(object(Request)) in Router.php line 675
at Router->dispatch(object(Request)) in Kernel.php line 246
at Kernel->Illuminate'Foundation'Http'{closure}(object(Request))
at call_user_func(object(Closure), object(Request)) in Pipeline.php line 52
at Pipeline->Illuminate'Routing'{closure}(object(Request)) in CheckForMaintenanceMode.php line 44
at CheckForMaintenanceMode->handle(object(Request), object(Closure))
at call_user_func_array(array(object(CheckForMaintenanceMode), 'handle'), array(object(Request), object(Closure))) in Pipeline.php line 124
at Pipeline->Illuminate'Pipeline'{closure}(object(Request))
at call_user_func(object(Closure), object(Request)) in Pipeline.php line 32
at Pipeline->Illuminate'Routing'{closure}(object(Request))
at call_user_func(object(Closure), object(Request)) in Pipeline.php line 102
at Pipeline->then(object(Closure)) in Kernel.php line 132
at Kernel->sendRequestThroughRouter(object(Request)) in Kernel.php line 99
at Kernel->handle(object(Request)) in index.php line 53

完整的routes.php文件：

<?php
/*
|--------------------------------------------------------------------------
| Application Routes
|--------------------------------------------------------------------------
|
| Here is where you can register all of the routes for an application.
| It's a breeze. Simply tell Laravel the URIs it should respond to
| and give it the controller to call when that URI is requested.
|
*/
Route::get('/', function () {
    return view('welcome');
});