iMac 27" i7 quad core and Windows 7

FIX for black / blank / missing screen on 27" imac

FYI I believe all of this can be avoided it you have a second monitor to plug into the iMac. Rumor has it that it defaults to the Display port when finishing the install of windows 7.

Deleting the display driver from the c:\windows\system32\drivers directory did not fix the problem for me. Instead, it took me into windows and said "An unexpected error has occurred" and gives you the option of restarting and booting you back into the same screen.

Entering safe mode to disable the driver worked for me:


After it asks you to hit any key to boot from dvd,
hit F8 to bring up windows boot menu
Boot in safe mode

***Do not click OK to reboot the computer just ignore the dialog box***
SHIFT + F10 for command window

cd c:\windows\system32
run CompMgmtLauncher
navigate to device manager
I disabled a bunch of hardware but you probably only need to disable the video card.