Custom 404 error page in asp

I have created a custom error page using asp. When I upload it to my site to test that it works, it appears to run fine. I have set it up so that an email would be sent to me if there is a page that can not be found. I first tested the page to make sure an email would be sent to me and it works. Then I made sure that my server variables where be queried by printing them to the screen. But when I go in to IIS to point the 404 error to my new page and test it, the page is processed like straight html and not as an asp page. When I type in a bad url for my site the page pops up and shows my new error message but when i view the source for the page all the asp in the page is unproccessed and in the source code. Can someone please direct me to a solution...