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Cannot adjust brightness after Big Sur update

Hello, ever since I upgraded to Big Sur the toolbar brightness keys and the keyboard light do not work on my MacBook Pro 2017. Brightness indicator appears on screen and the buttons appear to adjust up or down, but the actual brightness does not change at all. I called apple support and followed their indications, went to the Genius Bar and they never found the answer except with Catalina brightness key do work. Can Apple fin a solution? Thank you

MacBook Pro 13″, macOS 11.5

Posted on Sep 5, 2021 10:18 PM

Reply
Question marked as Top-ranking reply

Posted on Sep 5, 2021 10:32 PM

angeles212 Said:

"Cannot adjust brightness after Big Sur update: Hello, ever since I upgraded to Big Sur the toolbar brightness keys and the keyboard light do not work on my MacBook Pro 2017.[...]"

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Reinstalling the macOS:

One option would be to reinstall the macOS. Perhaps the install was not 100% successful? Sometimes, when major changes are made to your Mac(i.e. update installations), system settings (i.e. for Brightness) become manipulated, technically. So, when reinstalling, nothing would be deleted. It's just that items that have become corrupted or deleted, would be replaced or reinstalled back to where they should be. Go Here: How to Reinstall macOS from macOS Recovery - Apple Support


Important: First, Back Up your Mac:

Create a Time Machine backup of your Mac, so that you can have something to restore your Mac from, should anything go wrong with the reinstall. Take this as a learning experience, knowing to always create a backup of your Mac, prior to making any major changes to it (i.e. update installation)

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2 replies
Question marked as Top-ranking reply

Sep 5, 2021 10:32 PM in response to angeles212

angeles212 Said:

"Cannot adjust brightness after Big Sur update: Hello, ever since I upgraded to Big Sur the toolbar brightness keys and the keyboard light do not work on my MacBook Pro 2017.[...]"

-------


Reinstalling the macOS:

One option would be to reinstall the macOS. Perhaps the install was not 100% successful? Sometimes, when major changes are made to your Mac(i.e. update installations), system settings (i.e. for Brightness) become manipulated, technically. So, when reinstalling, nothing would be deleted. It's just that items that have become corrupted or deleted, would be replaced or reinstalled back to where they should be. Go Here: How to Reinstall macOS from macOS Recovery - Apple Support


Important: First, Back Up your Mac:

Create a Time Machine backup of your Mac, so that you can have something to restore your Mac from, should anything go wrong with the reinstall. Take this as a learning experience, knowing to always create a backup of your Mac, prior to making any major changes to it (i.e. update installation)

Cannot adjust brightness after Big Sur update

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