During quickstart installation, it can be an issue in creating configuration.php. This is when the quickstart package, is not put it in the main directory of your site, but in a subfolder in that site.
To avoid this issue, the quickstart should be put it in the main site and not in a subfolder.
For example your site is www.yoursite.com. All the files which are inside quickstart should be in www.yoursite.com and not in www.yoursite.com/quickstart
To add the files in your site, should unzip first the quickstart zip file and use FTP to add it in your site.