How to establish your own internet store with osCommerce, USPS shipping, Paypal Pro payment and Coupons

If you want to sell something in the internet you have multiple options, like

• Open Amazon.com store
• Open eBay.com store
• kagi.com
• If you’re selling software/non-material goods you can use multiple services like share-it

If you want everything quicker and ready to pay more and have less control on your store – go ahead and choose any of those. This article is about building your store that will physically reside on your server and use 3rd party payment processor to handle your payments.


Because the instruction appeared to be fairly long I split it into multiple posts. This is the master post. The goal of these posts si not to replace the manuals you can get from official vendors, but to quickliy resolve questions I spent so much time for when I was establishing my store.

So, after some evaluation I decided for myselft that the best platform for selling stuff on your own website is osCommerce Online Merchant. It is free, it is very well developed, it is used in thousands of other places and you can customize it the way you need. So here is the step-by-step instruction of how can build your own store.

1. Install osCommerce
2. Configure USPS shipping module
3. Configure PayPal Website Payments Pro (US) module
4. Optionally install coupons module
5. Test everything
   1. For testing purposes I created one coupon with huge discount to make the overall payment really small.
   2. If you don’t use coupons just create some fake good that you’re ready to sell for cheap. Make it lightweight too so you pay for “shipping” less.
   3. Do entire checkout process just like you future customers will do
   4. If on the last step you’ll just get back to your shopping cart and see “Security Header is Not Valid” check your Paypal configuration information – most probably you entered login, password or signature incorrectly.