The Apple Watch comes with a nifty little feature that allows you to unlock your Mac by simply bringing it close to it. You will need to press a key, or move the trackpad/mouse, but it beats typing in a password every time you want to use your Mac. This is a great feature when it works, but sometimes, the connection gets broken and you may not be able to unlock your Mac using your Apple Watch.

Instead, you will have to type in your password and figure out what went wrong. Usually, you will be treated with the ‘Your Mac was unable to communicate with your Apple Watch’ error message. There are a couple of reasons why this can happen and a few simple ways to fix it.

In this post, we will show you how to get things back to normal if you come across this error. Remember, this feature only works with Macs from 2013 and later. It requires macOS Sierra or later on the Mac and watchOS 3 or higher on the Apple Watch. If you’ve got an Apple Watch Series 3, then it requires watchOS 4 and the Mac will need to be running on macOS High Sierra. You will also need to have enabled two-factor authentication with Apple and both the Mac and Apple Watch will have to be signed in to the same Apple ID. Oh, and if there is no passcode on both the Watch and Mac, then auto unlock will not work. Let’s get started.

Fix ‘Your Mac was Unable to Communicate with your Apple Watch’

This error appears when you’re trying to enable your Apple Watch to unlock your Mac. When you head to the Security & Privacy option in System Preferences of your Mac, and click on the option that says ‘Allow your Apple Watch to unlock your Mac’’, you are presented with this error after a few minutes. There are plenty of ways to fix this issue and we have listed down some of the easiest methods below.

Reboot Apple Watch and Mac

As always, the first thing that you should try is to reboot both the Apple Watch and the Mac. On your Apple Watch, hold the Digital Crown and the Side Button at the same time to hard reset the Watch. Hold the buttons until you see the Apple logo.

To reboot your Mac, click on the Apple logo in the top Menu bar and select Restart. That’s about it. Once the Mac reboots, you will have to enable Auto-unlock once again.

Check for Software Updates

Make sure that both the Apple Watch and Mac are running on the latest version of its software. Sometimes, the Bluetooth and Wi-Fi stacks on your Mac may be broken, and the only way to fix it could be with an update to the OS. It is pretty easy to update the software on your Mac. Open the Mac App Store, click on the Updates tab, and check if there are any updates for the OS. Update and try if the Apple Watch unlocks your Mac.

To update the software on your Apple Watch, you will have to use the Watch app on the connected iPhone. Launch the Watch app, select the ‘My Watch’ tab and then tap on Software Update. After updating the software, you will need to re-enable the Auto-unlock feature on your Mac. Try if the Apple Watch unlocks the Mac and doesn’t throw any errors.

Automatic Login

automatic login

Check if Automatic Login is enabled on your Mac. If it is, then you should disable it. To do so, click on the Apple logo in the top Menu bar, select System Preferences, and select Users & Groups, click on the Lock button below the page, and then click on Login Options. Here, turn off the Automatic Login option. Try if your Apple Watch unlocks the Mac now.

Reset Bluetooth and Wi-Fi

If you’re coming across the ‘Your Mac was unable to communicate with your Apple Watch’ error, then you could try to reset both the Bluetooth and Wi-Fi radios on your Mac and the Apple Watch. Auto Unlock needs both these radios to be enabled and working properly. Simply turn off Bluetooth and Wi-Fi on your Mac, wait for 15 seconds and then enable them again.

On the Apple Watch, swipe up from the bottom of the Watch face to reveal the Control Center and enable Airplane mode. Once again, wait for 10-15 seconds and turn off Airplane mode. Check if the error is gone. If now, you may have to delete the Bluetooth preference file on your Mac.

Delete Bluetooth.plist file on your Mac

Delete Bluetooth.plist file on your Mac

Several users have confirmed that deleting the bluetooth.plist file from their Mac has fixed the ‘Your Mac was unable to communicate with your Apple Watch’ error. Here’s how to do this:

1. Turn off the Bluetooth radio on your Mac from the Menu bar or from System Preferences.

2. Launch Finder and click on the Go button on the Menu bar, while holding the Option key.

3. Select Library and look for Preferences.

4. Now find and delete the file ‘com.apple.bluetooth.plist’.

5. Enable Bluetooth.

Check if the Apple Watch will unlock your Mac. If it does, then it’s all good. If not, you may have to re-pair your Apple Watch or reinstall macOS on your Mac. Let’s hope it doesn’t get to any reinstalls.

Re-pair Apple Watch

Re-pairing the Apple Watch is a frustrating experience. However, if none of the above works, you might have to do it. Follow the steps below.

1. Open the Watch app on your iPhone and tap on ‘My Watch’.

2. Select the Info button next to the Apple Watch name at the top.

3. Tap on Unpair Watch.

4. Repeat the pairing process again.

After everything is done, re-enable Auto unlock using Apple Watch option on your Mac. Hopefully, the ‘Your mac was unable to communicate with your Apple Watch’ error is now fixed.