New user to Macs. I have two external hd - My passport for backups (connects no issue) & I have tried two others for my Family Tree storage. One older black box and a new Seagate. Neither wants to reconnect. Have tried restarting, total reboot and no go. They seem to "go to sleep" after inactivity. My son-in-law somehow has made them reconnect but then they are shortly gone again. Would like to be able to have them reconnect/display without having to call him over every 2 day. Thanks!