HomeKit iCloud Data Syncing…

had the exact same issues since day one. And believe me, I tried EVERYTHING ever suggested. Even after numerous HomeKit resets and signing in and out of things, what finally worked for ME was ----- 1-Resetting all devices to factory 2- resetting HomeKit configuration in iOS settings 3 -deleting every HomeKit related app 4- sign out of everywhere you are signed in with iCloud. including any other iPads, iPhones, iPods, Apple TV. Etc. I even went to iCloud.com and clicked sign out of everywhere. 5- I then picked an app that supports all HomeKit devices. - I used IDevices Connected app- 6- do not download each products own app, IDevices app finds, pairs, and sets up your HomeKit without the need of the products own app. For ex. Instead of downloading Lutrons app, I found Lutrons smart bridge 2 within IDevices app, I scanned the code, and set all products up in IDevices. There were one or two products that needed their own app but I don't remember which ones. Since I did that, any and all of my devices are accessible remotely and even work for fluently with Siri. And I had MAJOR issues with HomeKit and this seemed to work for me. I even got the new Apple TV and just set it up like normal, and my HomeKit is still working flawless. Hope this works for you and anyone else having any HomeKit issue. Good luck.

I am suffering the Sync Error as well. I have reset my entire HomeKit config countless times and keep ending at the same spot. I can configure all devices and everything works with Siri. As soon as I log in with iCloud my HomeKit starts throwing the 77 Sync Error. All apps are affected.

I went through this once before and was able to login to iCloud after waiting overnight with no devices logged in.

I am going to try that again but this is very frustrating.

I had the entire HomeKit (20 lights, ecobee3, iSwitches) working with Siri through the Apple TV 3rd Gen. It was awesome but only lasted a day... The problem really appears to be with the iCloud accounts.

OK, so I waited overnight and logged in with my Apple ID this morning. As I suspected, my HomeKit is now locked up with the HMerrorDomain 77 or iCloud Data Sync Error. I am unable to activate Remote Access or make ANY changes to the HomeKit config. Also it appears my ecobee3 has stopped talking to Siri. I can still control the Hue system with Siri but the thermostat is not being found. All devices work in their respective apps. Elagato Eve is showing the HomeKit hierarchy intact still.

I guess I'll wait and see what happens. I reprogrammed the entire HomeKit setup several times yesterday and can't go through it again.

Does anyone know if this Data Sync Error eventually clears? I have waited several days to no avail...

Any help would be appreciated, I've invested a lot in this system... It's great when it is working (without iCloud) but I need to be logged into iCloud for other tasks.

I reset Network Settings under General while I was on LTE. This immediately cleared up the error I was getting in ecobee3. After logging into my Wi-Fi again, HomeKit appears to be functioning. I am not getting Siri control through the AppleTV 3 like I had before though.