My parents live in AZ and I live in MN.  When they needed help, I used to have them share their screen with me via iChat, and solve their challenge.  However, now when I use Messages and FaceTime, the Share Screen is listed under the BUDDIES tab, but is not highlighted.  Therefore I am not allowed to share their screen or share mine with them.  Does anyone know how to make it so I have this option again?   Thanks!