iMessage not Syncing between iOS & Mac devices since installing iOS 11.01

Welcome to the Apple Support Communities!

I understand your iMessages and text messages aren't in sync between your Mac and your iOS devices since updating to iOS 11.0.1 yesterday. In addition to the troubleshooting steps you've already taken, I would suggest revisiting the settings for your Apple ID and checking that all requirements for Continuity are still in place.
I. Update your Apple ID Settings:

1. From your Mac, go to the Apple ID website and sign in with your Apple ID and password.
2. In the "Reachable At" section, confirm that your Apple ID (which is an email address) is listed, and confirm that the telephone number for your iPhone is listed. If not, click the Edit button and add that information. Click Done and sign out of your Apple ID account.

II. On your iPhone and iPad:

1. Open the Settings app
2. Tap Messages
3. Scroll down and tap Send & Receive
4. Make sure your Apple ID appears at the top of the iMessage screen
5. Make sure your Apple ID email address and your iPhone cell number are listed in the "You can be reached by Message at" section.
6. On your iPhone, start new messages from your cell number. On the iPad, start new messages from your Apple ID (email.)

III. On your Mac, review the instructions again for Continuity Settings
Use Continuity to connect your Mac, iPhone, iPad, iPod touch, and Apple Watch

If you have an iPhone, the text messages that you send and receive on your iPhone can appear on your Mac, iPad, and iPod touch as well. You can then continue the conversation from whichever device is closest to you.

Set up SMS and MMS messaging

Use this feature with any Mac, iPhone, iPad, or iPod touch that meets the Continuity system requirements. Make sure that your devices are set up as follows:

• Each device is signed in to iCloud with the same Apple ID.
• On iPhone, go to Settings > Messages > Send & Receive. Make sure that the Apple ID at the top of the screen is the same Apple ID that you're using for iMessage on your other devices. Add a check to your phone number and email address, so that you can be reached by iMessage at both. Do the same on your iPad or iPod touch.
• On iPhone, go to Settings > Messages > Text Message Forwarding, then choose which devices to allow to send and receive text messages from this iPhone. If you're not using two-factor authentication for your Apple ID, a verification code appears on each of your other devices: enter that code on your iPhone.
• On Mac, open Messages, then choose Messages > Preferences. Click Accounts, then select your iMessage account. Make sure that the Apple ID shown here is the same Apple ID that you're using on your other devices. Add a check to your phone number and email address.

Use SMS and MMS messaging

To use this feature, just start conversations as normal in the Messages app on any of your devices. You can also start a conversation by clicking a phone number in Safari, Contacts, Calendar, or other apps that detect phone numbers. All of your incoming and outgoing messages appear on all of your devices.

IV. Turn off your Mac and your iOS devices.
V. Unplug the power cable to your modem and/or router. Wait a minute, and plug it back in. This will reinitialize your connection to the internet and your Wi-Fi.
VI. Turn on your Mac, turn on your iOS devices
VII. Create a new message to test.
R22183, if your issue persists after trying all of these steps, reply back to this thread with any additional information you can (including any error messages you may encounter) and we'll investigate this further with you.
Take care.

I've been dealing with this same issue. Called Apple and it turns out somehow my phone number and Apple ID were on my blocked list. Checked your block list and see if your information is there. If so, remove it and your issues should be resolved.

Use Continuity to connect your Mac, iPhone, iPad, iPod touch, and Apple Watch - Apple Support

Read and follow that, before anything else.

Having a Bluetooth off or a tab swiped the wrong way will be like device is not there.

Hi,

I have the same issue and those steps didn't help in my case. After the computer has been turned on for a few minutes, imessages stop coming in. Very very frustrating ...

2016 Macbook Pro High Sierra 10.13

iPhone 6S IOS 11.0.3

My reply is in fact not an advice. It is addition. I have the similar problem. The only thing different is that the messaged gets synced when I send a message prom my phone which is strange. And what is even more annoying I lost even notification to my Watch 😟

MacOS High Sierra 10.13

iOS 11.0.3

Thank you for these suggestions.

iMessages used to sync between my iPhone and Mac without any problem. In the last 6 months or so Message on the Mac has stopped syncing. I have tried all the steps above and I keep hitting a wall when going to Mac > Messages > Preferences and trying to log in with my Apple ID. I keep entering everything correctly and I get a error message saying

"Could not sign in to iMessages - An error occurred during activation. Try again."

I know that I entered my Apple ID and pwd correctly since it works for everything else.

One important clue may be that when I go Mac > System Preferences > iCloud , I see a list of apps that are checked for iCloud connection such as iCloud Drive, Photos, Mail, etc... but Messages does not appear as an option. That does seem weird, doesn't it? Could that be the problem? And if so, how do I get it back there?

I'm on OS 10.12.6

Thank you for any help.

Bo

Settings----> messages-----> blocked......if your information is located on that list, you should be able to tap the edit at the top right corner and delete your number and/or apple id from the list.

Thank you. I checked that and my number was not on there.

I keep thinking it has something to do with the fact that Messages disappeared from the list of options for my iCloud settings on the Mac system prefs for some strange reason.

Hi Baudouin- I'm afraid the lack of Messages in the iCloud System Prefs isn't the answer. Oddly, for a supposedly centralised control of iCloud features, Messages does not appear there; I don't remember if once upon a time it did, but if it did, it hasn't for a long time now...

I'm afraid the Messages failing to sync is a me-too problem here... Honestly, with High Sierra- especially since the start of December when the "Month 13" error kicked in (check you Console if you haven't seen it)- everything is falling apart :-(

This Mac user of, hmmm...- 23 years- is about to give up- or maybe launch a class action suit against Apple for effectively trashing all my devices.. ;,-((

Wow... did I just dream this? I thought for sure Messages was in the icloud prefs both on the Mac and on the iPhone. Now I don't see it on my iPhone either... I swear it was there a few weeks back...

Ryan.p, you are my HERO! I have iPhone 6+, iPad Mini 4 and iPad 3 (and iMac, but don't care about messages there). No problems with first iOS 11 version, but with 11.1.2, messaging quit syncing on the 3 devices. Have spent HOURS on phone with tech support, followed by a Apple senior tech advisor & problem still not fixed. I just found my cell number in my blocked list. Unblocked it (just had to do it on 1 device), and did a messaging test with a friend and it all synced. Thank you!!!

I usually don’t update iOS devices until the update has been around for a few weeks, to prevent frustrations like this one. The only reason I did this one was because it was around Xmas, and I thought security might be important.

This drove me absolutely nuts for weeks as well!

I passed this on to the senior tech advisor that I spent HOURS with on the phone yesterday so maybe it will help others as well.

Happy New Year, and thank you again for taking the time to post your solution!

Hi there,

Thanks for your solution.

Have tried but it doesn't seem to sort out the problem.

When I send a message from my phone, that message is shown on my MacBook Air. However, when I get a message on my phone, don't see it on my laptop.

My laptop is running OS 10.12.4, and my phone is running 11.2.1

Btw, anyone has the problem that ID touch doesn't work all the time after upgrading to iOS 11.2.1? It works for me sometimes, and sometimes doesn't.... Quite annoying though.

Thanks for your help in advance

Did you have the button replaced by NON apple people?

If so that's the reason, and other phones like the 6 it will brick your phone (updates after home button non-apple.)

There is some kind of connection link in there that can get affected, don't remember what they called it, but had similar thing on a laptop where in the airport it was hit, and the wire came loose. My friends phone had that happen, and I wasn't there but they told him about it not properly communicating some how.

I've got over 10 years in, and I am with you......****** OFF!

Between the Messages no longer synching, computer crashing on wake from sleep, not able to change mic from Internal Mic to my Bluetooth headphones....the list seems to continue to grow.

All of the above worked within the last month, except for the sleep issue.

If Apple doesn't get their act together, it may be time to move on.

MBP 2017 15-inch

MacOS Sierra, 10.12.6