iMessage not syncing across devices after macOS 26.0.1 update

I had a similar Messages sync issue on Macbook with latest OS 26, where the sync will just pause itself. Asking it to resume sync does nothing. I have plenty of disk space and I logged out/in of iCloud, reboot, etc. nothing seems to restart the sync process. Then, just for fun I plugged in the Macbook's charger (it had 76% battery charge so I didn't think it was necessary), but after 15 seconds on the charger, the sync started itself back up! So it seems that not being on a charger for iPhones & laptops might cause the Message sync process to pause itself until it's plugged back in.

I had synching issues and here's how I fixed it. On your phone go to Settings>Apps>Messages. Scroll down to Text Message Forwarding. Check to see if your devices are listed and selected.

Plugging in the charger didn't fix the problem on my mac os26. Apple is aware of the problem and issued a tech note to it's CS advisors acknowledging the issue and that they don't have a fix. Apple rushed the release of Tahoe because of it's AI enhancements, obviously with minimal concern that it might not be ready. I'm erasing my drive and re-installing Sequoia. This is a major gaffe and reflects the insane greed that drives bad decisions.

This latest update of Tahoe is horrible! Sometimes my iMessages will crash and other times it won't even open. The solvent is this...Open Finder, Shift+Command+G and you will see this come up...~/Library/Messages/. Click on the first search that comes up and you should then see files labeled, chat.db, chat.db-shm, and chat.db-wal. You will delete those files and then iMessages should open and work. If you've got iCloud backup on, then everything will filter back through and be restored, but it might take a while. I've had to do this numerous times having updated to Mac iOS Tahoe 26 and Mac iOS Tahoe 26.0.1. It sucks and I'm not sure why Apple hasn't come up with a fix yet. Very frustrating!

[Edited by Moderator]

yess!!! my MacBook Pro, iPhone, Apple Watch Ultra, iPad mini, iPad Pro all have a different number of “read“ blue dots and notification tallies. Had Apple Support on the phone and after a period of time the call was disconnected. I received a case ID via email and no fix. I had already tried everything, from removing VPN, to turning on the message sync on each device manually, restarting each device, signing out of iMessage and back in. And nothing helped.

Everything has been done and redone. Every device is listed and the account is chosen. I have turned messages on and off. I have restarted phones. I have restarted laptops. I have restarted iPads I have restarted watch. Nothing corrects this. And as far as I have searched, this is a known issue and there is no fix thus far.

My issue is that SMS messages (I don't know about RCS because I have not received many lately) are all received on my devices (iPhone, iPad, Mac), but when I read on one platform so the message is marked as read, it is not marked as read on the others. I believe this started with iOS 26.1. It is not quite the same issue mentioned here, and I was thinking of creating a new discussion, but has anyone else seen this?

My iMessage only goes to my laptop and I'm not getting messages on my Iphone. Some messages are missing. I did the software upgrade, but still the same issue. I have tried all methods to get it to work. I rely on this for employment and I'm missing jobs.

That is the exact issue that brought me here. I am hoping to find a solution soon.