What does ' Attempting to submit a form from an unverified url' refer to?

As a security feature, ActiveDEMAND will only accept form submits from verified URLs. The website domain that you set up for your account is automatically verified (i.e. ActiveDEMAND will only accept web form submits from a page on your main website domain). If you are receiving this error, your webform is is deployed on a different domain than your main account domain.