Solution if Apple watch is not opening your Mac

[aardy]

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Unlock with Apple Watch on Big Sur - Tech Support - MPU Talk (macpowerusers.com)

Unlock iMac with Apple Watch

this one (think it’s the same solution) on the MPU forum worked for me, fixed it completely. Thanks to @aardy Steps (follow at your own discretion) Open “Keychain Access” In “View”, enable “Show Invisible Items” Search for “Auto Unlock” You should see a whole bunch of application passwords for “Auto Unlock: XXXX’s …” Select all records and delete (this will reset/disable auto unlock on other Macs if you use multiple Macs) Whilst still in “Keychain Access”, search for “AutoUnlock” (no space) T…