Contact 404 Error

I’m using the membership plugin, WP 3.3.1, looking on both IE9 and Firefox.

I’ve tried installing a variety of different contact form plugins (Contact Form 7 and Custom Contact Form among them) and keep getting a 404 error when I try placing their short code on the page.

Is there a contact form (NOT the Contact Form Widget) that will play nicely with the Membership plugin?