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Need to get laptop to display on external monitor when booting

I have a MacBook with a bad display which I am using with an external monitor. I have already replaced the video/isight cable to no avail and I'm not ready to spring for an lcd just yet. The problem with my setup is that I still have the original owner's password active to make changes and I don't know it. When I try to boot to disk to use the PW utility the MB won't display on external. Same for 'option' boot. I can't reinstall because I cant see what I'm doing. Is there a way to force the use of external monitor only?


Update to my comment bellow. I tried unplugging the Video cable and inverter (just in case) and I can boot to 'option' mode. Unfortunately as soon as I insert the Disk and then choose that as the boot option the screen reverts back to stretch mode with the OSx wallpaper. I can't even tell if the disk install/utilities desktop is up. I also tried the 'c' boot option and same thing. I'm stuck with

the previous owner's locked install. I can't even scan for updates!

Answered! View the answer I have this problem too

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my guess is the display is not mirrored in the settings so its just off to one side. does anything appear on the external screen?

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I can use the external w/out any issue during normal use. It switches between mirror and stretched w/ F7 key. The problem is that when I try booting from disk or into option screen it seems to disable the second monitor option. I was hoping there was a startup key press

option (since Apple seams to have about a million) that

would force external along with other boot options.

All I need to do is boot into the disk utilities so

I can use the Password changer.

Does anyone know if leaving the internal video cable detached will force that same state?


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Hi, I don't know if this is the answer to your problem but you might want to read this Macworld article--link provided. I know it says Mac Mini but the procedure is the same. Good luck.

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Thanks for the link. Some interesting reading there! Unfortunately my problem is that I CAN boot to the 'Startup Manager' but when I choose a volume other than the main HDD my external screen becomes either disabled or goes into 'span' or 'stretch' and all the windows and task bars/menus are on the laptop's broken screen. F7 doesn't do anything then. It seems the only way to get around it is to either replace the LCD panel (assuming its the culprit) or buy/borrow another intel Mac to try

target mode. I have several PPC macs which, if I understand correctly, the MacBook can read but cant

themselves read the MacBook. I actually don't know anyone nearby who has an intel Mac so I'm at a bit of an impasse. Since I can't afford an LCD panel at the moment I may have to put this on the back burner and use the Mac as it is for a while. It's such an absolute mess from the previous owner though. I won't even go into some of the files I have had to delete already since this is a Family-friendly forum...


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staggerwing will be eternally grateful.
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