unlock Mac with Apple Watch

My iMac 24 used to automatically unlock regularly with my watch. Since the latest update it works sometimes but then stops working. All my devices have the latest update and I've restarted my Mac. Any ideas?

iMac 24″, macOS 13.3

Posted on Apr 1, 2023 7:10 PM

Reply
38 replies

Oct 19, 2023 12:42 AM in response to CG5050

Personally I think there is a bug in macOS (my Mac mini M2 Pro is fully up to date at Sonoma 14.0) or possibly in WatchOS (Watch S7, 10.0.1), because my experience is that if the watch is not unlocked (I have forgotten to do so in the morning) the Mac tells me that it cannot unlock using my watch because the watch is not unlocked. So obviously it is communicating with the watch well enough, and properly paired to it, to be able to tell me that.


But if the watch IS unlocked I just the text "Unlocking with Apple Watch" and a spinning cursor for a few seconds before it is replaced by the password field and you have no option but to type your password in.


I have tried switching watch unlocking off then on again a few times but this does not fix the problem.


Furthermore I can use the watch to confirm purchases and in place of typing my password when the Mac has been unlocked - it is just the actual unlocking after sleep that fails. Hence my conclusion that there must be a bug interfering with the unlocking process.

Oct 19, 2023 6:50 PM in response to ncollingridge

ncollingridge,


I don't think there is anyone on this board that would disagree with your assessment that there is a bug in either MacOS, WatchOS or both. For me Apple Watch unlock worked perfectly from inception up to the April 2023 13.3 Ventura update.


Regardless here is a possible solution. Please perform ALL steps in this exact order:

  1. Force your iMac to use (and stay on) your router's 2.4 GHz Wifi (not 5 GHz).
  2. Turn off "Watch Unlock" on Mac
  3. Turn off WiFi on iMac
  4. Shutdown iMac
  5. Shutdown Watch
  6. Unplug all USB and Thunderbolt devices. If your boot drive is an external thunderbolt, unplug for a minute and plug back in.
  7. Boot up Watch and iMac
  8. Unlock Watch
  9. Turn on WiFi on iMac
  10. Turn on "Watch Unlock" on iMac. If the first attempt at getting the pill indicator to stick should fail, move off of the "Login Password" menu and back on and try again.


At this point there is a 50/50 chance that iMac Unlock with Watch will work. If not, it may take a 2nd reboot of iMac and it will almost always work.


I find that sometimes functionality will survive many reboots and sometimes fails after the very next reboot and requires either the full the steps all over again or as in my case the abridged version below:

  1. Make sure iMac is still forced to use only your router's 2.4 GHz Wifi (not 5 GHz).
  2. Turn off WiFi on iMac
  3. Turn off "Watch Unlock" on Mac
  4. Shutdown iMac
  5. Turn on iMac
  6. Turn on WiFi on iMac
  7. Turn on "Watch Unlock" on iMac


Let me know how you make out. Post with any questions.


CG



Nov 5, 2023 8:22 AM in response to Ruff2102

This is very frustrating and as you can probably tell by now there is no ONE fix to this. And the fact is that there are MANY reasons why this may be failing, so the key thing is to try and figure our WHAT is causing this, and only then may you be able to apply an appropriate fix.


As it was mentioned earlier in this thread the 1st thing you should try is to run the following command in Terminal.


Step 1: Enter this in Terminal:

log stream --predicate 'category == "AutoUnlock" AND eventMessage contains "fail with error"'


Leave terminal running and


Step 2: Attempt an Auto-Unlock


Then check to see what error was returned in Terminal. In my case it appeared that I was getting a timeout error, specifically "ranging timeout error" which usually indicates a Wi-Fi issue, so I simply went into System Settings/Network/Wi-Fi/Details/TCP/IP and clicked on "Renew DHCP Lease" and my problem was fixed immediately without having to jump through any of the previous loops of turning things on and off, restarting, etc.


****** So add "Renew DHCP Lease" to the list of things to try.


If you get some other error (and I am sure you will) try and research and see what that error is related to, and you may be able to find the root of your issue.

unlock Mac with Apple Watch

Welcome to Apple Support Community
A forum where Apple customers help each other with their products. Get started with your Apple ID.