This process will delete your entire database and create a fresh Magento install. Don’t do this unless you are sure you don’t need your data.
- Download the demo from http://www.magentocommerce.com/download
- Extract the .zip or .tar folder on your local computer.
- Fire up your FTP client and FTP the media folder from the demo folder to the directory where you installed magento on your server. This will bring over all the demo images.
- Login into your database through PHPMyAdmin.
- Drop all the tables in the Magento database. Make sure you don’t have any data that you need.
- Import the .sql file that came with the demo folder from you local computer. This file will reinstall the Magento database with the sample content.
- Navigate to your site. You should now be presented with the Magento user agreement license. Accept it and re-enter your database information.
- Once you are done refresh your site and you should now see all the demo information.
That’s it. Let me know if you have problems!