Apple Watch won’t unlock your Mac? Try these fixes
Apple Watch can automatically unlock your Mac and be used to approve authentication requests across the operating system. Unfortunately, the function does not always work as advertised. Here are some fixes you can try if you’re having problems.
Apple Watch unlock requirements
You can unlock your Mac from mid-2013 or later with an Apple Watch running watchOS 3 or later.
You can check if your Mac supports this feature by clicking the Apple logo at the top of the screen. Then click “About this Mac.” Select “System report” under the Overview tab.
In the window that appears, click “WiFi” in the sidebar and look for an entry that reads “Auto Unlock: Supported” to confirm.
You must also be signed in with the same Apple ID on your Apple Watch, iPhone and Mac, with two-factor authentication enabled on your Apple ID.
Note that even when the function works “normally”you won’t do it always be able to unlock your Mac the first time with Apple Watch. Just like using a fingerprint scanner, your Mac occasionally requires you to enter your full password to unlock (especially after restarting).
You may occasionally get “signal too weak” errors when trying to unlock, even if you’re sitting right in front of your Mac. This is more common on older Apple Watch models; we have noticed that quite a bit happens on a Series 4 while the watch is otherwise engaged in a training session or taking a call.
If you’re getting errors or your Apple Watch doesn’t even seem to try to unlock your Mac, there’s a good chance you can do something about it.
Check your unlock settings first
The first thing we recommend is to check to make sure you have enabled the service on your Mac and then turn it off and on again. You can find this option under System Preferences (System Settings) > Security and Privacy tab “Generally”.
There should be an option for “Use Apple Watch to unlock apps and your Mac” or “Let Apple Watch unlock your Mac.” Check the box if it is not already checked. If it is, uncheck it and check it again.
Then test the feature by locking the Mac. Click the Apple icon at the top of the screen and then “Lock screen”. You can then press on “Esc”key to put your Mac to sleep.
Be careful not to wake up your Mac by pressing the fingerprint reader button. You should feel two taps on your wrist when your Mac unlocks with the watch.
Restarting your Mac and Apple Watch is also worth a try.
You can restart your Apple Watch by holding down the side button, pressing “Current”icon at the top right and move the slider “Slide to turn off” right. Press and hold the side button again to launch it.
Deactivate and reactivate Handoff
If you see the error “Mac could not communicate with Apple Watch”- error, disabling and re-enabling Handoff can potentially fix the problem. When we tried this solution, Apple Watch unlocking started working immediately.
You can find the Handoff setting under System Options (System Settings) > General. At the bottom of the window you will see an option for “Allow handoff between this Mac and your iCloud devices”which you can uncheck and check again.
Go back to System Preferences (System Settings) > Security and Privacy. On “Generally”tab, make sure you have Apple Watch Unlock enabled. Now use Apple > Lock Screen to lock your Mac and test the feature.
Delete Auto Unlock Keychain Access entries
Many users report that manually deleting the auto-unlock entries in Keychain Access resolved Apple Watch unlock issues (with commenters on Apple Support Communities and Reddit citing it as a solution). It’s probably worth a try if all else has failed and you’re anxious to get the feature working again.
Note: Doing this will also reset and disable Auto Unlock on other Macs. Please note that if you go through with this, you will need to re-enable the feature elsewhere.
First, open the Keychain Access app on your Mac (search for it with Spotlight or find it in Finder > Applications > Utilities). click on “View” at the top of the screen and make sure that “Show invisible items” is enabled (it will read “Hide invisible entries” if you have done it correctly).
In the search field in Keychain Access, search for “Automatic unlocking” and select and delete all entries displayed (use Command+A, right-click and “Delete” the party).
Now repeat the search for “Auto Unlock” and find four entries: “tlc”, “tlk-nonsync”, “classA” and “classC”. Delete these too.
Finally, open the Finder and use the Go > Go To Folder option at the top of the screen to navigate to
~/Library/Sharing/AutoUnlock. You will see two entries named “ltk.plist” and “pairing-records.plist” which you can also delete.
Now go to System Preferences (System Settings) > Security & Privacy and try re-enabling Apple Watch Unlock on the tab “Generally”. You may need to try to enable the feature more than once, as the first attempt may fail.
Remove and pair your Apple Watch again
Removing and re-pairing your Apple Watch is a hassle, but it should only cost you time.
To do this, open the Apple Watch app on your iPhone and tap “All watches” at the top left of the tab “My watch”. Press “in”button next to the watch you want to remove, followed by “Disconnect your Apple Watch”and then follow the on-screen instructions to back up and remove the watch.
Once you’ve done that, go back to the Apple Watch app and tap “Add clock” on the screen “All watches”. You have the option to restore your Apple Watch from a backup.
When you’re done, try re-enabling Auto Unlock under System Preferences (System Settings) > Security & Privacy > General.
Ongoing errors may be to blame
If you’re still having problems, the issue may be the result of ongoing bugs in a new version of macOS or watchOS. Make sure your Apple Watch is up to date under Watch > General > Software Update (and it can’t hurt to update your iPhone too).
If you are determined, you can file a bug report with Apple. If all else fails, you can always use the fingerprint reader on your Mac to unlock it, provided your Mac model has one.