See also http://forums.macrumors.com/showpost.php?p=7221295&postcount=20

When you go to edit com.apple.RemoteManagement.plist with vi, and you notice that there is content already in the file, place the code supplied BELOW/AFTER the content, on a new line.

As well when you go to try and edit com.apple.ScreenSharing.launchd wuth vi, it may be helpful to unhide the file from an ls command with this:

echo -n enabled > com.apple.ScreenSharing.launchd

FINALLY, after your system reboots, before trying to remote administer with VNC, go into the System Preferences panel, click Sharing, then go to the Remote Management item. Click the Computer Settings button, and from the drop-down, select 'VNC viewers may control screen with password:' and enter your new password. (as Arjan said above, deselect "Anyone may request permission to control screen")

Hit OK.

I suggest a reboot one more time, and then try logging in with VNC.

Works for me now!

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