System requirements:
PHP Version 5.0 or greater is required.
MySQL extension must be enabled in php.ini
GD extension must be enabled in php.ini
File_uploads must be enabled in php.ini
zlib must be enabled in php.ini
Session.auto_start must be 0 (disabled in php.ini
In Apache httpd.conf DirectoryIndex index.php (index.php must be specified as a default start-up file name)
Make sure the following folders and files are writable. For Linux/Unix use the following:
chmod a+w image/
chmod a+w image/cache/
chmod a+w image/flash/
chmod a+w cache/
chmod a+w download/
chmod a+w config.php
This is the basic directory and file layout you need to achieve when uploading your files and folders.