In our system we use ASP.Net WebForms pages.

We have a self registration web page in our system where a user can come along and register to start using our system.

We have recently discovered that one of our clients are posting form data to that page from their website which in turn submits the form on the page.

We want to stop this from happening. We don't mind if they embed the page into an `IFrame` because it won't work correctly anyway. But we need to stop them from posting form data to that page from their system / website.

Is there an attribute that we can set or something which stop external posting to that page? Or perhaps an other alternative, Ajax seems to jump to mind?

Not quote sure what to search for, did a quick search online but couldn't find anything.

**Reason for wanting to Prevent this:**

When something goes wrong on that page, the user trying to register does not get any error messages back from our system so we are getting a ton of support about this. Surely we can add functionality to support but we would rather not. Also want to prevent bot attacks on that page because each submit will create a user if they do not exist.