I believe the majority of the SharePoint sites are set up to use Windows Active Directory login. However if the site is set up using a domain name, IE will treat it as a “Internet” zone, and you will be prompted with login window. That’s because the default security setting of Internet zone is not to automatically login with your user name and password.
The best practice to get around this issue is to add your site to the “Trusted Sites” list, and configure it to automatically login (which is the default setting already). Sometimes the Trusted Sites list is locked by a corporate group policy and network admins have to make that change. You have to run
to refresh the group policy on your desktop.
If you want to add multiple sites to the Trusted Sites, this syntax will do it: