Internet Explorer IE11 launches in Enhanced Security for Users despite setting in Server Manager

Our users log on to an RDP server running Windows 2008 R2. I have already gone into Server Manager and disabled ESC for both admins and users. While the setting is applied for admins, users still go into ESC when they launch IE11. I’ve already checked the registry settings and they reflect the appropriate settings from the Server Manager.

What else can cause users to launch into ESC?

Can a user tell IE to start without ESC?