There are several users for this laptop (Dell Latitude E7250), and each logs in to his/her own profile when using it. One of the users accidentally deactivated the touchpad on his profile, resulting in a cursor that won't move on his profile and only his. We've searched for a solution but can't find one. For instance, there is no Fn key that has a picture of the touchpad. It's got volume, brightness, wireless, sleep, etc, but no touchpad. And we don't have a mouse to use. What likely simple solution are we missing?