Can't unlock macOS High Sierra with Apple Watch Series 3

I tried everything.

Changing Mac password

Disabling/enabing Handoff

Unpair/repair Watch

etc.

None of these helped because my Mac was looking for some outdated token on my Watch.

Finally reached out to Apple support. This worked:

1. System Preferences > iCloud > turn off Keychain

2. Keychain Access > Preferences > Reset My Default Keychains

3. Reboot Mac

4. You'll be asked to enter your iCloud password - enter it, then give iCloud time to sync up.

5. System Preferences > Security & Privacy > Click the lock to make changes (ensure it's UNLOCKED - if it already is, skip this step)

6. Check Allow your Apple Watch to unlock your Mac

Because I never signed out of iCloud, and deleted my iCloud data, my Mac didn't have to redownload anything. Instead, it did a quick sync-up.= after I entered my iCloud password.

How to unlock your Mac with your Apple Watch - Apple Support

Use Continuity to connect your Mac, iPhone, iPad, iPod touch, and Apple Watch - Apple Support

System requirements for Continuity on Mac, iPhone, iPad, iPod touch, and Apple Watch - Apple Support

Hi - for me none of the posted solutions worked or then they were too radical. I was not prepared to gamble with a sign out of iCloud accounts on all devices due to the slow internet and the big amount of data.

What worked - simple fix - was a change of my Apple ID Password. When the system asks if you want to force a sign out on the others I answered NO. Then I have to just enter password again on all phones, watch, computers and restart all systems - I had to do twice as I did not follow order and then it worked. All in all 30 minutes to get it fixed.

Good luck.

I have spent hours & hours trying to get my 1st generation Apple Watch to unlock my iMac late 2014. I did everything apple said and everything everybody suggested, with no joy. Then I received a call on my iPhone and I noticed that my iMac did not ring at the same like it normal does. So I went into faceTime preferences and signed out then back in again. (I remembered I had this problem before and this how I got the iMac to ring again with my mobile number, set calls from iPhone ticked on) I also signed in & out of Messages on the iMac. I then called my Iphone to make sure the iMac rang at the same time which it did. Then I went back to security & privacy general and ticked Allow your Apple Watch to unlock you Mac & bugger me it worked. I hope it works for you, good luck. WolF

New Update 8 Oct 2017 I have this problem usually after Mac OS updates. All I do now is sign out of FaceTime on my mac, then close FaceTime then open it again and sign in again. Then open system preferences, security general and check that your Apple Watch is showing up under allow apple watch to unlock your mac and the box is ticked for your watch. this also fixes if my mac cannot use my Iphone to make and receive calls. Good Luck WolF

I have a similar issue. This happened to me after I updated my iPhone 7 Plus to iOS 11.0 and to the latest Watch OS 4.0. This feature was working when I updated my MBP to High Sierra but fails now that all three are at the latest OS’s. I created another Admin profile using the same iCloud/iTunes account info and it worked. My thought is my user profile got corrupted somewhere along the way. I’ve worked with Apple on this and they had no answers.

Any suggestions??

Hi my glitch seems to be related to having an old mobile me account that I had to use with iCloud when mobile me got closed down a few years ago. I was not allowed to use my iTunes account for iCloud, so I have an old mobile me account for iCloud, messages and FaceTime and a separate account for iTunes music and apps. My wife has just one Apple ID account for both iCloud and iTunes and her Watch has never missed a beat unlocking her Mac. The latest Mac OS update broke my Watch unlocking again but just signing out and back into FaceTime on my Mac does the trick. Good luck WolF

Sorry my workaround didn't work for you. Sometimes its just best to take a break and then start from the beginning following Apple recommendations first then trying the most recommended community workaround that worked. Good luck WolF.

No problem... appreciate your posting of the workaround, was clearly laid out. (also, appreciate the animal user name, we have a calif. fish and wildlife permit for african spotted cats... no wolves except for fursuiter friends)

No worries just a quick one. Just had glitch with AirPods not working with Siri after latest supplement update. Just a thought as the Watch series 3 has the latest version of Bluetooth. maybe turn off & on Bluetooth on your Mac, Watch and Iphone. Just a thought.

Best regards

Wf

This did it for me - and to save others any headaches in case you're not clear on where to find these commands, I've annotated the instructions a bit with my experience and a couple clarifications:

__________________________________

1. System Preferences > iCloud > turn off Keychain (I elected to leave them on my Mac rather than delete)

2. Keychain Access > Preferences > Reset My Default Keychains (the Keychain Access app is in the Utilities folder, and this will spit out a minor caution message once you do it - go forward anyhow)

3. Reboot Mac

4. You'll be asked to enter your iCloud password - enter it, then give iCloud time to sync up. (This hung at the "sync" step for me the first time, and I had to Force Quit System Preferences and try again - second time it worked)

5. System Preferences > Security & Privacy > Click the lock to make changes (ensure it's UNLOCKED - if it already is, skip this step)

6. Check Allow your Apple Watch to unlock your Mac

______________________________________

And there was much rejoicing...

I just got my first Apple Watch (Series 3) and spent hours this evening trying to get the Mac unlock feature to work. I finally called Apple support, who confirmed I had all my settings correct. We stumbled on the answer when the tech told me to turn off all the sharing options. She'd misread the Apple article (which actually tells you to turn off Internet sharing--a different thing, which never was turned on), but amazingly, it worked. We tested a few times, and the unlock feature appeared directly tied to whether or not the screen sharing/remote management setting was on.

That was sort of disappointing, as I have a home and a work Mac on different levels of my house and quite often use screen sharing to check mail or get documents from one computer to another. I really didn't want to have to remember to change the settings just to get the unlock feature.

But with a bit more playing around, I discovered it's not a problem for me to have the screen sharing/remote management setting on, AS LONG AS I'm not currently sharing the screen of the computer I'm working on with another. As soon as active sharing of this computer's screen begins, the unlock feature will not work until the sharing stops. I've tested it repeatedly and that is consistent behavior.

Just thought I'd share the info, in case it helps anyone else.

It turns out, I just lost the passwords temporarily. They were saved in iCloud and thus were immediately available on my iPhone and iPad and eventually available (the next day after everything synced back up) in Safari on my MacBook.

See if this thread is applicable: The message "Your Mac was unable to communicate with your Apple Watch" Keeps appearing when I try to set up my Watch to unlock my MacBook Pro