How do I remove a page from the browser history?

Question

I have an have an ASP.Net page which contains a button. This Page contains a ServerSide Paypal button.

When pushed my server does various clever things on the back end a

Answer 1

I'm not sure if that can be done. But here is an idea how you could prevent that resubmit of the form.

You could insert a hidden input in your form which at the beginning would be empty. On submit you'll write a value in that field and make sure you check on every submit attempt if this field is empty.

If it is not empty on submit you know that the form was previously sent and you could warn the user.