This tutorial shows how to create downloadable products in osCommerce.
1. Open osCommerce administration panel and create new product.
2. Go to Configuration > Download section and switch Enable Download feature value to True
3. Now go to Catalog > Product attributes and add new attribute Download with 2 options Available and Not Available
4. To create a downloadable item you should create a ZIP archive with the files that can be downloaded and put the ZIP archive into the downloads directory of your osCommerce installation.