How to fix 'Use Touch ID to unlock your Mac' grayed out on Magic Keyboard for Mac mini M4 Pro?

Hi everyone,

I wanted to share a solution that worked for me in case anyone else is experiencing this issue. I use the Magic Keyboard (Bluetooth, wireless) with Touch ID, which has been incredibly convenient for unlocking my Mac mini M4 Pro, making Apple Pay purchases, and accessing saved passwords.

Recently, I noticed that Touch ID stopped working after waking my Mac from sleep, forcing me to enter my password manually. When I checked Settings → Touch ID & Password, I found that the option to “Use Touch ID to unlock your Mac” was turned off and grayed out, preventing me from enabling it again.

To fix this, I simply connected my Magic Keyboard to my Mac mini using a USB-C cable. As soon as I plugged it in, the keyboard reconnected automatically, and Touch ID started working again. It seems that occasionally, a direct reconnection is required—possibly for security reasons.

Hope this helps!

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