Apple Watch can't always reconnect

Hi there! There isn't really enough information to debug the issue here. Would you mind filing a Feedback for this and make sure to include a sysdiagnose and devicectl diagnose ? Thanks!

I have the same issue. I was not able to connect the watch even once. I have submitted the feedback report. Please, prioritise this, because it seems that it is a very common issue and it's a huge blocker.

Same Issue on Xcode 15.4 and the las version for IOS, WatchOS and MacOS.

Same issue here. It has made developing for an Apple Watch very annoying

It's a complete joke nowadays. I stopped 4 years developing for AppleWatch because of the miserable tools situation. Guess what… it's even worse these days.

Same issssssssssue!!!!!!

This usually fixes the issue but the fix is not always permanent:

1. Quit XCode
2. Disconnect from your wifi on the Mac
3. Turn it wi-fi back on
4. Build the app again by selecting the Apple Watch as the build target.

Same issue here. Xcode 15.2

I have a same issue. Xcode 15.4, Apple Watch Series 5.

Hi folks. Sorry you're having this issue, but to date I don't think I've seen any reports come in with the data that Myke mentioned above.

With the transition to CoreDevice last year, we saw significant improvement in watch development, especially with S6+. S3-5 are a bit more challenging due to some difficult hardware constraints, but even those should be much better than things were when we were hopping through the phone with the previous device stack.

This particular error message is a bit confusing and needs to be cleared up, but essentially we are likely continually loosing connection with the device while trying to prepare it (mount the DDI on it).

There are a few known issues on all platforms regarding device prep (DDI mounting), but watch is indeed the most problematic. We WANT to fix these issues and will engage with anyone that is willing to provide us with data to diagnose such problems.

The most important thing here is to ensure we have a high quality network connection for both watch and host. Enwure bonjour traffic isn't blocked (which is common in corporate networks). Don't cheap out on low quality networking gear!

The best triage steps here are to drop below Xcode and run xcrun devicectl device info ddiSeevices --verbose --device <ID> and surface up that full error and timestamp with your bug report.

Please include the FB number here and include a link to this reddit post in the feedback report, so we can connect the two together (and ensure your report gets routed to me).

Regarding bugs with Apple products:

1. Don't assume that Apple engineers know about an issue just because you complained about it in forums or reddit or whatever. Bugs that are filed with Feedback Assistant generally get to an engineer within a business day. Comments in forums don't.

2. Don't assume that just because someone else filed a bug report that you don't have to. The vast majority of feedback reports that I see (I'd estimate 98% or more) are not actionable and almost all of them don't get a response back from the reporter when requesting more information. If you are serious about getting a bug fixed, then please take action and file that report because your investment in working with us is what will help us understand the issue and get it resolved.

3. If you are serious about engaging with us and not just submitting a "+1", then be sure you:

   a. Change the title away from the default. This makes your radar stand out as likely containing more than just click-through data.

   b. Provide solid repro steps (what hardware is involved, network config, versions, steps, etc).

   c. Provide ample logging. In the case of any device connectivity issue, please provide diagnostic logging by running xcrun devicectl diagnose after reproducing (ideally with our logging profile installed per https://developer.apple.com/bug-reporting/profiles-and-logs/?name=CoreDevice). Please ensure that the resulting devicectl diagnose contains sysdiagnose from the host and relevant devices. If it does not, please collect those manually and include them as well.

Hope that helps!

--Jeremy

Thanks for the insight, last night I was facing this issue and indeed it was extremely frustrating.

Closing xcode did not help "reset" anything. However, turning off the Mac did work.

Next time I am in the middle of a dev session and my watch refuses to connect, I will grab logs as you have guided.

FWIW, I do triage work for the other side... Dealing with these kind of intermittent failures is quite a nightmare in the triage world.

Also, AFAIK, there are no exact repro steps.... Something goes stale and connections are refused. By reset, I mean the problem went away automagically.

1. Tuning off/on the watch doesnt reset
2. Tuning off/on xcode doesnt reset
3. Turning off Mac did reset (M1 Air 2020)

Ran into the issue again just now. Filed a feedback report FB16000502

Thanks! Taking a look...

@killuhwhale I am taking a look at the sysdiagnoses now. It seems like you didn't attach a sysdiagnose from your Mac. Can you collect a sysdiagnose and attach it to the feedback report, please?

As a side note: if you are able to reproduce the issue again, please collect a sysdiagnose from your Mac and devices right away.

Thanks!

--Hassan

Facing the same problem. Filed a feedback report with devicctl diagnose and sysdiagnose logs.

FB16122816 (Xcode cannot install app in Watch SE 2)

Resetting the wi-fi seems to do the trick.

The solution to the issue for me was to restart the computer

Always the same problem. Does not stop.

I submitted a report, but that sys file just kept saying "gathering..." for a long time, and I didn't see a reference number to offer

But, turning the WiFi off and on is working for me as well

I face this problem daily and have not found any way to fix other than building 1000 times and eventually it connects. I lose so much time over it, I really wish it would get fixed.

Any updates here? This is the first watch app I've built and it requires testing on a device and I'm simply unable to do it.

I'm developing using my old Series 4 and experienced similar issues: endless "transport failures", connection issues, connection drops, etc.

What you need to understand is that all those issues are likely to be caused by your wifi infrastructure. For example: Series 4 can only connect to 2.4GHz wifi... while your Mac and/or phone can do both 2.4GHz and 5GHz. The thing is that in more and more places, both networks are joined under a single hotspot name... My Optimum ISP even calls this "SmartWiFi". Well, let me say that: there is nothing smart about it. On paper, your MacBook, phone, and watch are connected to the same network, but in fact, some of them could be on 2.4 and others could be on 5GHz networks. Thats what always causes those issues with debugging. If you have a similar situation, you need to ask your ISP or network administrator to separate 2.4 and 5GHz networks into different names and make sure all your devices connect to the same network. In my case I connected everything to 2.4 and haven't had connection issues ever since.

There is also a workaround if you work in a public space where you cannot do anything about it. The solution is to use your phone as a hotspot and manually tell your watch and MacBook to connect to it.

Hope that helps...

Will this problem ever be solved? The Apple Watch was released in 2014 — it’s now 2025, and this issue still hasn’t been fixed. Maybe that’s why there are so few apps for the Watch: because the debugging process simply doesn't work properly.

I’ve been struggling with WatchConnectivity for three weeks. I need to use transferFile, but it doesn’t work on the simulator. I sit for 8 hours a day staring at the message: "Previous preparation error: Transport error."

Once in 200 attempts, Xcode might manage to launch the app on a real Watch — and even then, the connection drops within 10–15 seconds. Not a single one of the thousand workaround tips fixes the problem. Endless reboots of my Mac, iPhone, and Watch; switching Wi-Fi and Bluetooth — it’s all useless.

Maybe you could finally release a Watch that can be connected via a cable? Maybe that would solve the problem?

I've noticed this always happens when the watchOS updates. This error was happening continuously after a watchOS update, I restarted the computer, then all the shared cached symbols have to be slowly copied from watch to macos.

Now facing this problem as new Apple Watch developer. What a pain. Nothings helps. Restarted, put WIFI on mobile hotspot etc.