Your Mac was unable to communicate with your Apple Watch.

After trying the other recommended solutions on the web including from apple support I determined that after upgrading my apple 4 watch to the apple 6 watch that my iMac would not "communicate" with my apple 6 watch. I also had a Mac Pro 13 with the most recent software and was able to set up the unlock routine with the apple 6 watch. This pretty much narrowed it down to the iMac being the problem. I guessed that it was still for some reason looking for the Apple Watch 4 that used to work on it. I tried the above solution and also found the "finder" autounlock folder by searching autounlock in the library folder. deleted those file also. I restarted the iMac and had to select the Auto Unlock box a couple of times and finally it worked. I don't know if this help anyone but thanks again for this fix.

Unable to get two watches to Auto-Unlock

I own a series 5 aluminum and a series 6 stainless watch. After unpairing and re-pairing the watches to get my fitness / activity / health tracking corrected, I am now faced with this issue of auto-unlocking my MacBook Pro.

I have done everything in this thread (following Mark's deletion of keychain files, turning keychain off/on in iCloud, restarting all devices, etc) and can only get one watch to be set for auto unlock. In the past I had two watches that worked perfectly (Series 0 and Series 5). I removed the Series 0 from my account when I purchased the new Series 6.

I can only get one or the other to remain set for the auto-unlock. I have spent literally hours trying to get both to work. Anybody else in this situation and have you found a solution? Thanks!

Now unable to get either watch to Auto-Unlock my Macbook Pro despite constant reboots / restarts / deletion of keychain items and pref files.... Followed all options in this thread and still can't get it to work. Time to give up until Apple engineers find a fix. Extremely frustrating.

Now i am facing another weird issue. When I started the MAC later, after the MAC locks and i click and button, the screen appears saying "Unlocking with your apple watch" but then it right away asks for the password. It doesn't unlock now...this is sooo frustrating ...any one have any resolution to this?

TiggerGTO-

Thanks so much for your persistence and followup. Much appreciated for the link to mark__t 's fix. As i posted previously, I was able to get that solution to work for one watch but when I went to add my 2nd watch, it wouldn't connect. After mulitple attempts to try to get both watches to work, I walked away assuming one is better than none. Several hours later, I tried to get my 2nd watch connected after wearing it for awhile. Amazingly, it finally communicated and I now have both watches working. My guess is there is a delay in setting up handshaking between the watch and my Macbook Pro. When I switch watches, sometimes I get "unlocking with Apple Watch" and then it prompts me for a TouchID. Seconds later, it'll work.

Hopefully Apple engineering will figure out this communication issue. In the mean time, for those that use two watches, I suggest following the above procedures, set up the first watch for auto unlock, put it away, put on your 2nd watch and let it be paired to your iphone for an hour or so. Then try setting up auto unlock for your 2nd watch. Finally worked for me!

yay - this finally fixed my problem!!! Thankyou!! I tried all of the same suggestions (restarting everything, making sure everything is on the same WiFi network, disabling/enabling handoff, restarting bluetooth, disabling/enabling auto-unlock of watch from phone, logging my Mac out of iCloud and back in again, etc.) but this is what worked in the end!

Apple has released a new update for the watch today; along with the instructions that Mark_t provided it worked, as initially didn’t like it. But after a reboot - the MacBook offered to link up the watch and booyah, it’s connected!

It worked OK after I updated my watch with watchOS 7.0.2 - But..........after shutting down my iMac (Catalina 10.15.7) and restarting it NO LONGER WORKS. Blast!!! I hope this will get sorted when Big Sur comes out?

The solution by mark__t worked for me. Just one observation. When you get to step 9 you might have a little problem with locating the Sharing/AutoUnlock folder inside ~/Library as it seems to be a protected folder. I like to use the terminal to get to stuff instead of the finder and saw messages like "operation not permitted" for listing (ls) or deleting those files as suggested in step 10. I had to go into the "Security and Privacy" widget in "System Preferences" and make sure that "Terminal" was added as an app for "Full Disk Access" under "Privacy". Simply using "sudo" on the command line does not grant elevated access. Other than that it did finally solve my mystery with not being able to use my Apple Watch to unlock my Mac.

Unfortunately this did not work for me after multiple attempts. I think I'll wait for a proper software update from Apple. There must be thousand of users with the same problem and they seem to have had these difficulties over a number of years and Watch versions.

I take back my remarks above. I left my MBP to do something else. When I returned I logged in as usual with a password, then miraculously a pop up appeared inviting me to turn on my Mac with Apple Watch.

Many thanks to mark__t and TiggerGTO and everyone else on this thread.

Yea, once it works it should be good. I noticed that the previous times I tried it, my "Auto Unlock: Watch Name" never populated in my iCloud Keychain. But once I did this, it showed up. I think that's necessary for Auto Unlock to work for any Mac. So once you have it, you should be good to unlock any Mac :-).

watchOS 7.0.2 re-broke my fixed unlock feature for my newly purchased watch series 6 ... now these procedures don't work to re-enable it ... "unable to communicate ... blah blah blah"

thank you iapple

This worked for me, I had to restart the MacBook after the last step and then going back to System Preferences, turning on the feature and having it fail once, it worked the second time almost immediately.

This was my identical experience. I went beyond and reinstalled Mac OS X on both my MBP and iMac and the problem STILL has not been resolved. Not sure what else to do other than wipe my machines and do a clean install, which I am not willing to do.