Mac not unlocking after watchOS 7 update

I've finally fixed it! I found a bunch of errors related to "AutoUnlock" in the Console that was hinting to me that there was some invalid state on my Mac with keys and plists not being reset properly. 

Steps (follow at your own discretion)

1. Open "Keychain Access"
2. In "View", enable "Show Invisible Items"
3. Search for "Auto Unlock"
4. You should see a whole bunch of application passwords for "Auto Unlock: XXXX's ..."
5. Select all records and delete (this will reset/disable auto unlock on other Macs if you use multiple Macs)
6. Whilst still in "Keychain Access", search for "AutoUnlock" (no space)
7. There should be 4 entries for "tlk" "tlk-nonsync" "classA" "classC"
8. Select 4 records and delete (don't worry if they re-appear, the system repairs this automatically)
9. Open "Finder" and navigate to "~/Library/Sharing/AutoUnlock"
10. There should be two files "ltk.plist" and "pairing-records.plist"
11. Delete both files
12. Open "System Preferences" and try enabling auto unlock. You may need to enable it twice, the first attempt will fail.

Didn't work for me.

Instructions all worked but still getting the same error every time I try and activate the Apple Watch unlock.

Tried re-booting multiple times and also signing out of iCloud on my Mac, phone etc.

Nothing is working

I had this issue also. I finally resolved it. Here's how:

Go to System Preferences

Click Apple ID

Click Overview

Sign out

Restart your Mac

Open System Preferences

Click Apple ID, and

Sign back in to your iCloud account

Go to System Preferences/Security & Privacy/General and check "Use your Apple Watch…"

Worked for me. Hopefully it will for you, too.

Reset the SMC and the PRAM. I tried all of the above suggestions. It still did not work. I opened a case with support on this issue yesterday morning. After all the verification and debug capture, they will get with the developers, analyze and get back with me next week.

Last evening when I logged into my iMac, I got the popup notification that Auto Unlock with watch was not enabled. Would I like to enable it. I did and it worked this time.

A guy on another forum posted this, and this kept it working for me. After taking the laborious steps above:

After spending hours trying tons of various suggestions for exactly the same issue, this suggestion solved the issue.

https://discussions.apple.com/thread/251803595

What I did after following the above (just in case it mattered):

1. Toggle "KeyChain" off and then back in iCloud settings on the Mac.
2. Restart the MacBook.
3. Then, went to enable the "Use your apple Watch..." checkbox and after 1-2 attempts, it worked!

It's not clear that anyone understands what the problem is. It seems likely the problem is caused by bad keys being synchronized from one device to another in iCloud Keychain. I suspect the problem can be worse when you have more i-Devices and Macs using iCloud Keychain. Sometimes unpairing Watch will fix, sometimes not. Usually stoska992's keychain process works. (If you search on MacRumors forum, you'll find an earlier post that provides this solution -- it contains a lot of discussion on steps when the keychain process doesn't work.) There seems to be some "strange magic" going on behind the scenes with iCloud Keychain.

If the solution worked for you in the past, then you might have some bad info in your keychain on one of your devices. You can try to clear this out by taking these steps... CAUTION: you may need to re-enter wifi passwords, website passwords, etc on your devices. You could loose those passwords if you aren't careful.

1. Make sure all Mac's and iDevices are turned on and connected to WiFi. Preferably the same wifi.
2. Turn off "Unlock this Mac with Apple Watch" on every Mac you have.
3. Turn off iCloud Keychain on each iDevice (but not Macs). When it asks if you want to keep the the data, say no. This will remove as much data from the keychain as possible.
4. If have more than one Mac, pick one to be your master keychain. This should probably be one you can unlock with Apple Watch. On all others, turn OFF iCloud Keychain, so that only one Mac has iCloud Keychain enabled.
5. Wait a little while -- 5-15 min or so should be ok. This is to give iCloud time to catch up.
6. Turn off all iDevices and Apple Watch.
7. On each Mac that is NOT the master, open Keychain Access and follow stoska992's process steps 1-11, even if it cannot unlock with Apple Watch. Then shutdown these Macs.
8. On the master Mac, with iCloud Keychain enabled, open Keychain Access and follow stoska992's process steps 1-11. Then restart the master Mac.
9. Wait about 5 min to be safe, then check Keychain Access and the directories in stoska992's process to make sure unwanted files and keys have not reappeared. (don't delete the 4 entries for "tlk" "tlk-nonsync" "classA" "classC") *** NOTE: If other items reappeared, turn OFF iCloud Keychain on the master Mac. This *should* remove all Keychain data from iCloud, leaving you with just what's on the master Mac. Then return to #8 above, and then turn iCloud Keychain back on.
10. Turn on iPhone and Apple Watch. Enable iCloud Keychain. Wait a few minutes (5-10).
11. On the master Mac, enable Unlock with Apple Watch. Test that this works. It should.
12. Turn on other Mac's and iDevices and re-enable iCloud Keychain.

All *should* be working at this point.

Hi stoska992, thank you so much for sharing these steps! it worked for me!

what's not working is when I try to use my apple watch to unlock another things like notes, it appears on the watch the animation, but when I double-tap nothing happens... any guess? (for unlocking the mac itself it's perfectly working, thanks again.)

I finally got it to work - logged out and in of my AppleID on my phone and my MacBook - see my reply in https://discussions.apple.com/thread/251826134?answerId=253559241022#253559241022 Hope that helps someone else too.

Here’s what fixed it for me, following steps originally posted here then adding a couple of steps added by others on this thread:

https://discussions.apple.com/thread/251826134?answerId=253529745022#253529745022 

FIRST, the 12 step procedure above:

THEN, this command in terminal provided by contributor “isprainedmyuvula” ( …a breathtakingly creative and silly handle):

sudo rm /Library/Preferences/com.apple.Bluetooth.plist && sudo shutdown -r now

…Which will restart your Mac.

THEN #12 above again. And just like stoska992 writes, it indeed took the second attempt at checking the box, and out worked instantly!

Sincere thanks for your advice, which I copy & paste below:

Click on "Finder". It is most likely to the left on your dick. Looks like this "//:0https://discussions.apple.com/content/attachment/39f9701e-2119-4c40-8df9-6eccbfcbb484

English is not my mother tongue, and it took me a while to realise that you actually meant "dock". Not that your instructions were essentially incorrect, you understand....

Before receiving your email, I had, out of desperation, searched for, and manually deleted the 2-files, and now the unlocking function works like a dream! Thank you very, very much once again, and God Bless.

Chee Thutt

I tried all the other options myself, including the selected answer on this. Nothing worked.

Spend an hour and a half with apple support and finally got the issue resolved. I reset the NVRAM on my macBook Air and it worked instantly. Quick fix as well. If nothing works for you, try using the link to reset NVRAM also.

Power down the computer.

Press (Option + Command + V + R) immediately on boot up, and hold for ~20 seconds.

Screen will flash a couple times (and make boot up noise). Wait for it to boot up 2x before letting go.

https://support.apple.com/en-gb/HT204063

I tried all the other options myself, including the selected answer on this. Nothing worked.

Spend an hour and a half with apple support and finally got the issue resolved. I reset the NVRAM on my macBook Air and it worked instantly. Quick fix as well. If nothing works for you, try using the link to reset NVRAM also.

Power down the computer.

Press (Option + Command + V + R) immediately on boot up, and hold for ~20 seconds.

Screen will flash a couple times (and make boot up noise). Wait for it to boot up 2x before letting go.

https://support.apple.com/en-gb/HT204063

I tried all the other options myself, including the selected answer on this. Nothing worked.

Spend an hour and a half with apple support and finally got the issue resolved. I reset the NVRAM on my macBook Air and it worked instantly. Quick fix as well. If nothing works for you, try using the link to reset NVRAM also.

Power down the computer.

Press (Option + Command + V + R) immediately on boot up, and hold for ~20 seconds.

Screen will flash a couple times (and make boot up noise). Wait for it to boot up 2x before letting go.

https://support.apple.com/en-gb/HT204063

Auto Unlock with Apple Watch works with FileVault and can be enabled when FileVault is on. When it's working, I unlock my FV-encrypted Mac Mini and MacBook Air frequently via Watch, and I have been since the feature was introduced some years ago. Apple doesn't mention any issue with FileVault. https://support.apple.com/en-us/HT206995

Maybe you are confusing "Automatic Login?" https://discussions.apple.com/thread/7985581

Auto Unlock cannot work in two situations: (1) When restarting your Mac, and (2) on a portable Mac once the RAM is powered off, which depends how you have your Mac configured for Sleep/Hibernate. In both these situations, a user password is required to unlock the FV-encrypted drive.

Unless your Mac has a T2 chip, I would never disable FV for an SSD.

SumNeuron wrote:

This no longer works after latest update macOS 11.1

What no longer works? I have a MBA 2019 with Big Sur 11.1 and it works just fine. See this support document, Unlock your Mac with your Apple Watch - Apple Support especially right at the bottom about turning off the Unlock selection, then restarting the Mac and turning it on again.