i try to install Laravel 5.1:
php composer create-project laravel/laravel --prefer-dist
and i have got this:
Error Output: Zend Guard Loader requires Zend Engine API version 220090626.
The Zend Engine API version 220121212 which is installed, is newer.
Contact Zend Technologies at http://www.zend.com/ for a later version of Ze
nd Guard Loader.
This issue is due to a value set within the php.ini file, which is probably searching for the wrong version number.
Check that these values are pointing to the right version of ZEND, or disable ZEND Guard Loader (the later is probably not the best)..
Hope that this fixes the issue for you.