I have a 2011 Macbook Pro with AE CS4. It has been working well mostly, but I tried connecting an external HD monitor through a mini port to HDMI connector. There seems to be a problem with the HD monitor, and after a few tries to get it working right, my AE window went black. I have scrapped the montor and now trying to fix the AE black screen issue. Nothing works to get rid of it - esc keys, etc. If I fast switch (apple>tab) I can get to my other apps fine, and I see the AE interface in the background. I have reparied permissions, zapped the pram, restarted. The mac is functioning fine, but when I open AE, it goes straight to the black screen and I cannot escape it. I suppose I can trash prefs, just haven't done that before, and want to be sure that is a recommended solution before I mess something up. Thanks in advance for all your help.