I have a page template that is am using as a basic, super-simple shopping cart. At step 1, it POSTs first name, last name, email, and a hidden field (step=2). This works. Then, it asks for credit card information. You fill this out, and it gives a 404 error.
the form action="". The page is http://www.mydomain.com/checkout for the first and second steps. /checkout DOES EXIST.
Something I am doing is blowing up the URI parse inside the wp engine. I can't figure out what.
Why would a 404 error be triggered when posting to a WP page even though that page itself exists?