iMessage: "An error occurred during authentication"

Hello,

I had this problem with my mac since the fall of 2017. I finally just figured it out. It seemed as though I looked everywhere to try to get it to work and nothing fixed it.

If you haven't fixed it yet, this is what worked for me.

1. Go to system preferences on your computer.

2. Click on iCloud.

3. Sign out of your iCloud account.

4. Restart your computer while you are signed out.

5. Once you have restarted your computer, go back into system preferences and sign back into your iCloud account.

This should do the trick. If not I can provide a link with other suggestions.

Hi!

I was having this same issue on my Macbook Pro (bought yesterday) after migrating over settings from my Mid-2012 Macbook Air.

I followed the Keychain Access instructions, but still received the "an error occurred during authentication." In my case, I logged out of Messages on my iPhone and Air. Then, on my Macbook Pro under "Accounts" where I was receiving the error, I clicked "forgot my password" and changed my iCloud password. I then logged back into messages on my iPhone and Air. For me, this solved the issue.

Perhaps my situation was unique since it seems a lot of folks have had to go through more complicated/lengthier steps. But I figure it can't hurt to try the above before having to get on the line with support!

Best,

Shrujal

I had the same issue but that my phone number being blocked/blacklisted for some reason. Head tech cleared it and then we:

1. sign out of iCloud on all device
2. sign back in on all device (one at a time)
3. signed into iCloud.com : added my phone number again
4. on iPhone / settings / message / send & recieve : click 'AppleID' and logged in. This prompted a popup on other devices to to add phone number to device.
5. on iPhone / settings / message / text message forwarding : turned on all device.

Hey! I had the same issue though on a different version of MacOS.( High Sierra). I called up Apple and a Level 2 cc executive fixed it. Apparently my Apple ID was blocked on the server. Sort of like reported as spam or whatever but now it works. This could be a solution to ur error too.

Peace out!

If it is not missing open Keychain Access in Applications/Utilities.

Have Login set top left.

Have Passwords set lower left.

On the right find the item that reads IDS: (yourName)@gmail.com-Auth Token and delete it.

Restart Messages.

^^^^Brilliant. Was without iMessage since High Sierra upgrade. Would never have figured this out without this tip.

Before you do any of the other recommended tasks, make sure you have a "Shared" folder with correct permissions. Here is how to add one if it's missing, it says for iTunes but it worked for me for all cloud programs (messages):

iTunes crashing with 'Access Privileges' error in 10.6.7 - CNET

I may have deleted my "Shared" folder in a misguided attempt at "cleaning up" my Macbook, I don't remember (frankly I think it started when I changed login passwords but whatevs, it worked). Apparently a lot goes on in the "shared" folder that we don't see.

Hi,

That info - to phone Apple - is in the Users Tip I first mentioned on 14th April last year and again in December

9:04 pm Thursday; February 15, 2018

Hi,

Thanks for the info.

This:-

Level 2 support said if that hadn't worked, the next step would have been to delete all Start Up launch agents and then restart allowing them to regenerate themselves.

seems a little excessive.

My Hard Drive/System/Library/LaunchAgents folder contains 282 items

I have another 7 items in Hard Drive/Library/LaunchAgents that belong to items I have Installed that are used by All Users.

For me the last seven are trusted items in that I know what they belong to (Java update info to run Adobe products, some Adobe stuff itself, the Little Snitch install and an item to do with my Printer)

There is one item there though that does refer back to when this Mac User Account was migrated from a G4 computer.

I do know that Apple are still looking into the cause of this and phone calls to Apple Support are likely to go through various changes as they eliminate stuff.

9:22 pm Tuesday; January 24, 2017

Hi,

There is a feature that is supposed to protect you from other computers trying to pretend to be you.

It seems it gets triggered for some people on a sort of almost random manner.

See When the iMessages account will not Login

7:47 pm Friday; April 14, 2017

You're welcome

7:23 pm Saturday; April 15, 2017

Hi,

You will need the link in the post I mead on the 17th April.

8:26 pm Saturday; June 24, 2017

This comment may belong elsewhere in the forums at this late date but when I had this same problem in Sierra, this discussion thread was the only one that continually popped up in my searches. I followed Ralph's advice (Thank you!) to the letter without success, then called Apple and followed the chain to Level 2 support where the first thing we tried, booting into safe mode (depressed shift key during restart) solved the problem. I hadn't needed to boot into safe mode since Yosemite so was rusty regarding what happens exactly. It doesn't just load the OS without third party apps and add-ons, it also runs repair routines. Booting took way longer than I ever recall but was immediately able to log into Messages and FaceTime (still in safe mode) and after restarting in normal mode all worked again as well. Level 2 support said if that hadn't worked, the next step would have been to delete all startup launch agents and then restart allowing them to regenerate themselves.

This problem manifested itself for me after my iMac power supply had a meltdown, and I replaced it. I am logged in into Messages on both my MacBook Pro and my iPhone.

I tried every suggested solution on these pages, and then some: no cure so far. I think I remember I had a very similar, if not the same, problem for a while when I did a clean install of El Capitan, early 2016. After a couple of days however, things returned to normal without any intervention whatsoever.

Any more ideas for a solution? What if I did a Time Machine or other backup restore?

Hi,

If you Migrate the whole Mac User's Folder over to the new computer your can effectively block your Apple ID when used by Messages for the iMessages to the iMessages server.

In the Keychain is the IDS item that stores info about the Apple ID, Password and the Serial Number of your Mac.

Whilst it is there to protect you it will become more Permanent if you don't do anything about it.

You will need this User TipWhen the iMessages account will not Login

It can be long winded Phoning Apple Support and getting high enough up the Responders to be able to get someone who can look at the server and tell if your ID is blocked.

8:42 pm Monday; December 11, 2017