I installed php 7.2.2 / apache 2.4 and mysql-5.7 on windows 10.

I want to install laravel 5.6

first:

```
1.  composer clear-cache
2.  composer update
3.  composer global require "laravel/installer"

```

php -v:

```
PHP 7.2.2 (cli) (built: Jan 31 2018 19:31:17) ( ZTS MSVC15 (Visual C++ 2017) x64 )
Copyright (c) 1997-2018 The PHP Group
Zend Engine v3.2.0, Copyright (c) 1998-2018 Zend Technologies

```

and `Laravel Installer 2.0.1`

I try this (according to the laravel doc 5.6):

```
composer create-project --prefer-dist laravel/laravel blog

```

But it install laravel 5.5.28

Why does composer keep installing laravel 5.5?