Question: I set up Laravel. But the 'artisan' didn't work. So I did like this.

\*

```
CCNI@CCNI-WS MINGW64 ~/Cilostan
$ php artisan --version
PHP Warning:  require(C:\Users\CCNI\Cilostan/vendor/autoload.php): failed to ope
n stream: No such file or directory in C:\Users\CCNI\Cilostan\artisan on line 18
PHP Fatal error:  require(): Failed opening required 'C:\Users\CCNI\Cilostan/ven
dor/autoload.php' (include_path='.;C:\php\pear') in C:\Users\CCNI\Cilostan\artis
an on line 18
CCNI@CCNI-WS MINGW64 ~/Cilostan
$ composer dump-autoload
Generating optimized autoload filesClass Illuminate\Foundation\ComposerScripts is not autoloadable, can not call post-autoload-dump script
> @php artisan package:discover --ansi
PHP Fatal error:  Uncaught Error: Class 'Illuminate\Foundation\Application' not found in C:\Users\CCNI\Cilostan\bootstrap\app.php:14
Stack trace:
#0 C:\Users\CCNI\Cilostan\artisan(20): require_once()
#1 {main}
  thrown in C:\Users\CCNI\Cilostan\bootstrap\app.php on line 14
Script @php artisan package:discover --ansi handling the post-autoload-dump event returned with error code 255

```

\*

then I did "composer update".
The updating was successful. However when I entered the server localhost:8000, the server error 500 occured. 

How can I resolve this problem? Help me, please.

Answer: 
As I could see from your error: 

> 
> PHP Fatal error: Uncaught Error: Class
>  'Illuminate\Foundation\Application'
> 
> 
> 

Seems like you're missing the mentioned file. The composer is trying to discover some package that has `Illuminate\Foundation\Application` file, but it can't resolve it, since it might be missing. Check if the file exists, if not, clear your `application` cache: 

```
php artisan config:clear
php artisan cache:clear
php artisan optimize

```

After that, try `composer dump-autoload` again.

If that still doesn't work, clear your application bootstrap cache manually, because it might cache non-exsisting files, which is located in `bootsrap/cahce` directory. You could see it's trying to locate the file there: 

> 
> thrown in C:\Users\CCNI\Cilostan\bootstrap\app.php on line 14
> 
> 
> 

So you could delete `bootsrap\app.php` content as well, or find the mentioned file and delete the line where it is mentioned.
first try this

```
composer install

```

it will import your packages and create vendor folder.
If you get error then first run

```
composer dump-autoload

```

then

```
composer install

```