If a page displays blank in the browser, it means there is an error on the page but error reporting is turned off.
add the following code at line 1 to turn error reporting on:
one problem I see in the code is that the Go to page is set to redirect back to itself. that means that if it does end the email out, it going to redirect back to itself afterwards, which will trigger the email to be sent again.
That redirect will send the page into an endless loop.