Got this message while using the composer install command:

[Composer\Downloader\TransportException]                                                                                                                         
  Your configuration does not allow connections to http://xxx.com:80/path/to/repo/repo-name-0.0.0.tar.gz. See https://getcomposer.org/doc/06-config.md#secure-http for details. 

Just run this command:

composer config -g secure-http false

Then, go ahead!

Referrence

[1]. Latest Composer version not pulling Laravel. https://stackoverflow.com/questions/36003429/latest-composer-version-not-pulling-laravel/38167033