First, make sure the index.php file is there. It may not have uploaded properly. If it is, then it sounds like your web server isn't configured to allow PHP files to act as directory index files.
If you're using Apache, create/edit your site's .htaccess file and add:
DirectoryIndex index.html index.php
More info here: http://www.htaccess-guide.com/directoryindex-uses(http://www.htaccess-guide.com/directoryindex-uses)
If you're using a different web server, you'll have to look up instructions specific to it.
Once that's resolved, the admin panel is located at /scp
