iMessage not working on Big Sur

So I too have been having the same issue since updating to BS. I have updated on 2 separate iMacs >> one device works like a charm, and the other iMessage is a "brick"

I tried the usual fixes >>

Starting with the APP itself: Sign out/ sign in of Apple ID; sync/unsync; untick 'enable icloud messages";

Supporting services: listed here >> proxy under wifi

System >> reinstall BS via recovery mode

All unsuccessful on the brick device.

The fact that one device works and the other doesn't would seem to debunk the idea that it is associated with the Apple ID being associated as SPAM and someone turned off at the Apple server. If that were the case, then the AID/iMessage shouldn't work on either device.

What I did find finally seemed to help on the Brick device:

1. Delete some of the imessages that have a fail, and re-start the thread with the individual
2. Voila... it worked... not scientific, but at least a respite from the pains of not having ability to send messages from my desktop.

So, if you don't mind deleting the text thread that is not allowing you to send the message >> try deleting and restarting new text thread with same individual, and see if that helps?

It worked for me... either lucky or just a Christmas miracle

Good luck and stay safe.

I had a similar problem: new Big Sur computer, not an upgraded one, and two SMS/green messages not going out from the Messages app on the new Mac. In searching for a solution this page was one of the first threads I found. Before I tried some of the involved steps others tried here, I found what seems to have been the solution for me on another web page (comment by Catalin Baciu) and it turned out to be SUPER-SIMPLE! I'll quote their solution here:

"Looks like text message forwarding was disabled on my iPhone.

On your iPhone, go to Settings > Messages > Text Message Forwarding and make sure your Mac is an enabled device in this list.

Restarting the Messages app on your Mac might be required for this fix to work."

As soon as I found the "Text Message Forwarding" the problem (for me, at least) was immediately apparent. I had 3 devices listed, and only two were enabled, and the new Mac was listed but not enabled. One tap to enable it and suddenly the two messages I'd tried to send out were able to go!

Hope this helps others.

The solution suggested is listed above in previous thread. However, i continued to have intermittent problems after my suggestion, and trying others. Here is something i tried yesterday and it seems to be working so far:

Under iMessage preferences, go to the second tab "@messages" settings; at the bottom, select to start all conversations from your mobile phone number and check the box with your mobile #, in the middle section "You can be reached for messages at."

Then uncheck everything >> so there are no boxes checked for any email addresses to receive texting on, the icloud and sync are also unchecked/greyed out. Now you should see a greyed out option for your mobile number at the bottom and in the middle. Now sign out and sign back in.

For whatever reason, this seems to be working for me thus far.

Good luck, and Happy Holidays!

Exactly the same for me, I called to apple support and they fix it in a couple minutes.

There seems to be iMessage fix's in latest 11.1 Public Beta 2.

At least my iMessage is working now (I could sign in, but no sync no matter whatever I did) after installing that one, so there is hope out there.

Ok I am going to take a shot in the dark here.

When you have the messages app open under preferences @iMessage tab do you see both your cell number and your email? Does your number show down at the bottom where it says start conversation from? Under blocked is there anything?

Thanks for leading me in the right direction. My Auto Proxy Discover was not ticked, but then I noticed that I had about 70 networks checked and I cleared them all out just because I am OCD and messages and FT started working again. I have no idea if that was actually the problem. Just glad it's working! :)

Messages on my 2018 Mac mini have not worked since upgrading to Big Sur. When I open the app and log in the wheel spins and eventually I get a message that says "An Unknown Error Occurred".

I am an IT Professional and a Mac user since 1985 - also a big fan of Apple.

I have been working with Apple Support for 20 days on this issue. They call me back when they have another thing to try. Here's what We've done.

Keep in mind it still doesn't work after trying all of these things:

• Booting into Safe Mode
• Reinstalling Big Sur
• Completely wiping the Mac, restoring it to the OS it shipped with, (Mojave) and reinstalling Big Sur
• Deleting the Messages DB items in the Library
• Deleting the Login Keychain and creating a new one

The person I've been working with at Apple is excellent. The issue is she has to wait for the engineers to get back to her with another thing to try.

I've spent many hours on the phone with her and many hours on my own trying to solve this issue.

If anyone has been able to resolve this issue, please let me know. Thank you.

I have had repeated issues since installing Big Sur (and I am on a third reinstall now -- one being done with Apple Support). The most prevalent problem is related to iMessage and iCloud credential authentication (though I've also had issues with Safari, etc.) Last week, I was on the phone with Apple for more than 2 hours because I couldn't make any changes to preferences for iMessage because of a credential authentication issue. The reinstall temporarily fixed it, but I was on the phone with them again yesterday for the same problem. They have scheduled me for an in-store visit. I was optimistic that the overnight update would address this issue, but...no.

And...I have a 2017 MacBook Air.

This happened to me on my MacBook Pro but just today after doing the Big Sur 11.2.1 update. UGH! Apple support has had me launch from safe mode, reset SMC and reset NVRAM. I tried all the Apple ID things everyone suggested and nothing works. They also said nothing is wrong with my account. They want me to reinstall the MacOS but I'm seeing some have tried it with no success. WTH Apple!?

can you share what they did to solve it please.

Do you remember what they did to fix it?

I came across the exact same issue .....I have contacted Apple support,they fixed it in a flash

I don't really get you..... if your facing problems with iMessages/FaceTime on BigSur check the below given link for support from apple they will fix it for sure

https://getsupport.apple.com

I am having the same problem, after I updated I was not able to sign in at all, I sign in, and about a few moments later it prompts me to sign in again. I re-installed macOS Big Sur, and it did not resolve my issue. Even restarting the Mac, and not using it for a few days didn't fix my issue. I thought it would be fixed in a patch, but there hasn't been a patch since Big Sur came out. I would love to fix this.