I have an eCommercer website built on open source code. Currently when someone purchase a product they get a download link via email. The link is generated via a php script that takes the static product link then creates a dynamic link that expires after about 5 days. We are having a few issues where people are trying to download the products and are getting error messages or incomplete file downloads. I need someone to evaluate this issue then suggest a solution. Additional information will be provided to providers that have strong experience in php site development or trouble shooting.