So I noticed with SharePoint sites if you are using IE, it automatically sends your AD username/pass to the server. Now I'm being asked if the same can be done with the other internal websites. The other websites are written in php and I don't have access to the server settings, just to the php scripts. I did find a way to authenticate against AD from php scripts once the username and password gets submitted to the scripts. So I'm like halfway there once the script knows what user/pass, the user wants to use it can check if it's valid. but what I still need to know is how to tell IE that this page needs to know the user/pass they are logged in as like the SharePoint site pages can.