Help with typing text in websites

I use this code to automaticly type text in a username and password on the site i want to login.

WebBrowser1.Document("Username").Value = "Test"

I used this line in the website's source to get the username textbox name:

<input type="Username" name="Username" value=""


But when I try to do this on one of the sites, I can't find the username box name. It looks like this in the source:

<input type="hidden" name="areaID" value=""


Is there a way to type text into that textbox by using the WebBrowser. .... .Value = "Test" ?