Verifying Secure HTML username and password?

I am trying to create a program that will check a users details to see whether they are eligible to enter a secure HTML site (where a box comes up and says enter network password).

If the user enters the wrong username or password, I want to disallow them access to the site. I am more interested in verifying the USERNAME than the password.

I have made a program using the Microsoft Internet Transfer control with it's Protocol property set to HTTPS (Secure HTML), that will send a username and password and then download information on a page. The problem with this way is that I enter a URL to download, and if the wrong details are entered, i just get the page that is displayed when you enter wrong user details. Understand what I'm saying?

I just want to be able to verify that the user has entered the correct username or password to enter the site. I don't want to download anything. If anyone can provide any samples or ways forward I would greatly appreciate it. Thanks.

Laterz ppl.

REM