Apple watches cannot be updated to watchOS 26.6 after iPhone gets updated to iOS 27

Fixed: What actually fixed it: a hard reset from the watch's physical buttons, not through the Watch app or Settings.

1. Press and hold the side button until the power-off icon appears in the top right.

2. Press and hold the Digital Crown until "Erase All Content and Settings" appears.

3. Tap Reset, then confirm by tapping Reset again.

After that, pairing and setup went through without the update loop. Apple chat/phone support and in-store Geniuses couldn't resolve it any other way — this button-based reset was the one thing that worked.

Hello everyone,

I recently struggled with an update loop on my son's Apple Watch SE 2 (managed via Family Sharing on my iPhone 17). After updating my phone to iOS 27, I couldn't connect to the watch (which was on watchOS 26.2) through the Watch App.

When I tried unpairing and setting it up again, I got stuck in a loop where it forced a watchOS 26.6 update but repeatedly failed with an "Unable to install update" error.

Here is how I finally solved it:

1. I paired the watch with a friend's iPhone running iOS 26.6.1.

2. On that iOS version, I was able to skip the update during setup. This option is presented.

3. Once set up, I went into the watch's storage menu and deleted the partial watchOS 26.6 download.

4. I unpaired the watch from my friend's phone.

After that, I was able to pair it with my own iPhone successfully. The update still took about 1.5 hours to complete, but it worked without any errors. It seems like a corrupted partial download was the root of the issue.

I hope this helps anyone else experiencing the same problem!

Dave

Update: I’ve even pulled out an old iPhone 13, updated it to iOS 26.7, and I still get the same error message the OP of this thread is getting when I try to pair (which REQUIRES am install of Watch os26.6 update) to iPhone 13 and iOS 26.7. I’m not a tech-savvy guy, but that makes me think it’s a WatchOS 26.6 update issue, not an iOS 27 issue. To further that belief, I have two watches - a Watch series 6, and a Watch Ultra series 1. Both of them WERE paired to both of my iPhones, but now neither of them will pair to *either* phone (running either iOS 26.6 or iOS 27) - unless I update to WatchOS 26.6 - which gives me the error code and won’t install. But….why did my Watch 6 stop paring with my iPhone 13 Pro Max and 17 Pro Max in the first place when I haven’t even tried to update IT to WatchOS 26.6 like I did my Ultra 1? I’m confused, and broke from all the Apple products I buy.

Hello!

Have the same problem. iPhone 16e, iOS 27 and Apple Watch SE 2gen.

I can’t pair my watch because of update. It seems need to wait for iOS update with fix this bug.

these forums are user helping other users like yourself, it's sort of going to a physical apple store and asking other customers their advice

This is a user helping users with tech questions forum, we are not apple and apple do not read your posts here

You can provide them with feedback using Product Feedback - Apple

Or reach out to their official support channels

Get Support (apple.com)

And or

Contact - Official Apple Support

And or

Contact - How to Contact Us - Apple

Or

Genius Bar Reservation and Apple Support Options - Apple

Same problem. Trying to restore from an older iPhone on iOS26 but not having a ton of success. WatchOS 26.6 just hangs on Verifying.

Things I've tried:

• Unpair, re-pair on iPhone 17 Pro w/ iOS 27 (fail)
• Unpair, re-pair on iPhone 16 Pro Max w/ iOS 26 (works, hangs on Verifying)

I've tried all manner of combos of resetting, restarting, restoring, and it just isn't working. I hope Apple addresses this soon because I don't want or need a new watch (this one is barely four years old!).

Another option is, I did it without unpairing

1. connect to power
2. connect to wifi
3. from the watch itself, go to storage and delete the watchOS
4. the watch will recognize there is an update and it will download the watchOS. Or should be 1.4GB.
5. the all process will take a while

The only thing you need to do is to remove the broken download using Storage option on watch. It is one and only remediation on official support page for Apple Watch Update process: Update your Apple Watch - Apple Support so hard to believe someone did not get help from phone support.

No need to unpairing, pairing with older OS, magic combinations of hard resets, or other destructive methods. Once the download is removed operation can be performed from iPhone without any issues.

See post from emon_ganguly; this worked for me

Thank you. Deleting the watchOS worked. Even the authorised Apple service centre did not know this. They declared the watch dead! Almost bought a new one.

I have totally the same issue with my iPhone 13pro on iOS27 and Apple Watch 8 that don’t won’t to start working even after reset before installing Watch OS26.6, but that is unable to install for a dozen tries. Now I have totally unusable Apple Watch and I’m really upset that I can’t find a solution for this.

I’m not criticizing your point, because it’s likely true, but the fact that it’s likely true. An “Apple Support Community” that doesn’t include Apple itself in that support isn’t even like going to an Apple Store and speaking to customers - its like going to a McDonald’s drive-thru and asking if they have an iPhone and can help you. I mean, the OP of this thread even said they contacted all the links you post here, and even went into an Apple Store, but no Apple employee in any of those outlets could fix the problem for them. So, although you’re likely right (Apple’s not present here) it feels like you’re sending them to the McDonald’s drive through.

Neither watch will pair to either phone, so I can’t get to the storage area in the Watch App. to remove the file. The Ultra was reset, so I can’t do anything on it because it wants to pair to setup (and I get the same error you got even trying to pair on iOS 26.6). My Series 6, which I have not reset - won’t pair to the iOS 26.6 because it thinks it’s paired to the iOS 27 phone - but it doesn’t show up in the Watch app on either phone.

Just spent the last 40 mins with Apple tech. If you have an Ultra ( first gen) and already updated your phone to iOS 27, you are done. The watch will never connect to your phone again. They suggested pairing it with another iPhone with iOS 26 on it but it wont let it update until they have updated their phone to 27. Cheers Apple.