I just hooked up a new secondary monitor to my imac via hdmi-thunderbolt connections and encountert 2 major problems:
1. My mac cant detect the monitor!
Its a software problem because on my bootcamp win 7 it worked just fine.
2. As soon as i started win 7 with the monitor attached (it worked and showed the same stuff as my normal one) the mouse stopped working. Ive had the same problem before when i had set up my lan cable, but cant remember how to fix it. Ive tried everything like restoring an older version from 2 days ago andit worked for 5 seconds and then stopped again. (Theo mouse does still work in mac OS, the problem begins at the win 7 log in screen)