[Qvistgaard]

My TV is connected to my iMac (MiniDVI-to-DVI + DVI-to-HDMI) so that I can watch videos on my TV. The TV is never disconnected from my iMac so when i go to Sys.pref>Display my TV is always there, even if turned off. This means that when I use QuickLook to preview items from my desktop it will preview on my TV (even if turned off). If I preview items from a folder it will appear on my iMac as its supposed to!

My question is then, how do i make QuickLook preview ALL items on my iMac no matter if my TV is connected or not?

[P]

Quicklook windows show up where it was when you closed the last one. Open one window with your TV on, drag it back to your Mac and close it again. Future windows should show up on the main screen.

[Cold Warrior]

If your TV is off, then your Mac just isn't realizing it. Use the Detect Displays option in System Prefs > Display to get it to recognize its single monitor.

P's solution will work best for you though.

[ibook_steve]

Originally Posted by Cold Warrior 

If your TV is off, then your Mac just isn't realizing it. Use the Detect Displays option in System Prefs > Display to get it to recognize its single monitor.

P's solution will work best for you though.

I don't think this will work. The computer is detecting the adapter connected, not the TV itself. Maybe it's different with the way the OP has it set up.