So problems arise when i click on the "add to cart" button on the product's page i get a
Error 404: NOT FOUND!
Your browser cannot find the document corresponding to the URL you typed in.

It only happens after i edit some php files. ( only the ones listed on the Top 10 Questions page in the wiki) the footer, congratulations message, and the tagline text, any clue if this would have an effect on this?

and i know for a fact that the add to cart button works because i have tested it out before... the original problem came about when i added a new template also...