Snow Leopard Upgrade Gotcha: Black Screen

When upgrading to Snow Leopard, I encountered an apparent bug. I started the upgrade process and walked away for a couple of hours. When I came back, the screen was black and the machine appeared unresponsive.

I assumed that the upgrade failed. Thanks to the backup program SuperDuper, I booted off of the backup, and started to restore the computer from the backup.

In the mean time, I searched in Google for an answer. I learned that the upgrade was successful, but the screen blanker had activated, and would not turn off. I let SuperDuper restore the computer to try again.

How to Avoid the Problem

Before upgrading to Snow Leopard, go to System Preferences, and click on the Energy Saver. Make a note about the position of the Display sleep slider.

To avoid the problem, move the Display sleep slider to Never. If it warns you that this will take up more energy, ignore the warning. This is a temporary action.

Upgrade the operating system per the Snow Leopard instructions. You should not encounter a black screen if you walk away. Go to the System Preferences, click on Energy Saver and restore the Display sleep setting.

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4 Responses to Snow Leopard Upgrade Gotcha: Black Screen

  1. Philipp says:

    And if you forget to do this, use a flashlight. This guy had the same problem and figured out that you can see enough if you point a flashlight at your screen to complete the install. Here are the detailed instructions:

    This is a seriously annoying bug. Disappointing to get this from Apple.

  2. Thanks for pointing this out, Philipp. Had I known that at the time, it would have saved the re-install. 🙂

    I, too, was surprised that Apple missed this one. I hope they added it to their test cases.

  3. JV says:

    Hi there.

    I’m having the same problem.

    How did you use SuperDuper?? with an external display??


  4. I booted off of the external drive. When you boot the Mac, hold down the option key to get a list of bootable drives.

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