Mojave 10.14.4 fails to Authenticate Gmail account

I don't think any call to technicians will fix things. Nothing will fix the bug until Apple roll out an update to Mojave but there is a workaround.

There is no need to delete accounts. Just turn them off, make them inactive so you don't lose your On My Mac emails.

Then add your Google accounts using manual IMAP settings. You must also use app specific password server side on Google.

Your emails will now work whilst Apple issue a fix.

I had a number of Gmail accounts with this problem - although not all my Gmail accounts were affected. I got tired of waiting for a fix from Apple, so here's the workaround I used on all of them:

1) Quit out of the Mail app if it's running.

2) Completely remove (not just disable) the affected account(s) from System Preferences > Internet Accounts.

3) Log into https://accounts.google.com/signin/v2/identifier.

4) Click on Security, then click 2-Step Verification and make sure it's OFF (if you don't do this, the next step won't even be an option).

5) Set "less secure app access" ON.

6) Re-add the account(s) from System Preferences > Internet Accounts.

7) Launch the Mail app - the account(s) should sync.

AndreD's solution worked for me, as well, and I'm using a G-Suite account. The steps were slightly different, but it worked ... where nothing else did previously. My steps:

1. Uncheck all G-Suite syncing from the Internet Accounts preference pane.
2. Close System Preferences.
3. Open System Preferences > Internet Accounts, and choose Calendar for syncing.
4. Get a popup asking me to authenticate. Choices are "Cancel" and "Open Safari."
5. I chose "Open Safari" and went through all the authentication procedures I had previously.
6. Like magic, I'm in.

I don't know why this worked, and I don't know if all these steps are necessary. I simply (and desperately) tried to mirror AndreD's solution as closely as possible. I won't look a gift horse in the mouth, but I did want to validate that there's something here. Disclaimer, FWIW, I only sync my calendar, because our company policy doesn't allow me to use desktop clients for email. So your mileage may vary.

I tried every work around posted and the ONLY one that worked for my Gsuite account was the Charles Rewrite. I had to repeat on my two Macs. Here is the process I followed. If this guy figured it out why can’t the Apple engineers fix it? https://forums.macrumors.com/threads/mac-mail-app-broken-for-some-gmail-users-in-macos-mojave-10-14-4.2175312/page-4#post-27232575

This is what works for me:

1) Delete the Gmail account in your computer.

2) Using the browser, change your Google password for a new password.

3) Install your Google account again from scratch and use the new password.

This is work just perfect for me.

Finally a 100% working solution is very simple.

In safari: logout from your google suite account (to make sure you will fix the right one).

Go to https://accounts.google.com/DisplayUnlockCaptcha to repair the access (documented on https://support.google.com/accounts/answer/2461835?hl=en)

after fixing add the account in the mac os settings or over the mail app as usually (you don't even need to delete it first if it's already added).

After verification in the opened safari window everything will go well.

The trick was simply to fix the password with the google link

This is what I did and it works:

1. Logon to your google account (not the Gmail account)
2. Click on "Security" left panel
3. Scroll down and find: Less secure app access
4. Click on "Turn on access"
5. Google will notify you of the changes--click "yes"
6. Go to you Mail account(s) and delete your Gmail account
7. In Mail click Mail >> Accounts
8. Click "Add another account"
9. Choose "Mail account" (just below AOL)
10. Type in your Gmail account info
11. That's it!

I had the same issue of Mail logging out of gmail, and tried some of the suggested workarounds to no avail.

SOLUTION: What worked for me is to copy the Mail app version from my backups before the 10.14.4 update, and put in utilities folder. I launched from utilities folder and has been working ever since with no problems.

Just make sure you quit out of Mail app, and copy the app from your Time Machine backup drive (Not from the Time Machine app).

This is a common problem now, but one person's solution doesn't seem to fix everybody's problem.

I would suggest closing the gmail accounts on your Apple Mail (system preferences - internet accounts - deleting the gmail accounts by clicking the - sign.).

Then close the gmail accounts on Google on your browser. (if you reopen the accounts later, the data will still be there)

Then reboot your Mac, and reopen the gmail accounts on their web site.

Then set up the gmail accounts on your Mail again, by going to System preferences - internet accounts and instead of pressing the + sign or the Gmail link, press 'Add Another Account (do not use the Google link)'. Then press 'Mail Account" and enter your data.

Let me know if this works for those of you with problems. Mine was fixed by resetting up the gmail accounts as in one of the previous paragraph. I think the problem is with the Google link.

Cheers

In my MacBook Pro 2018 10.14.5 didn't solved.

I solved deleting my gmail account and adding a new account NOT using gmail preset, but using Other Account in System Preferences, Account. Then I unchecked everything but the mail flag.

I found a way to eliminate the endless loop. 

1. On your MacBook go to>system preferences, then choose >internet accounts. 

2. Click on Gmail and then choose the remove “—“ at the bottom. If Gmail cannot be highlighted/removed, first select “mail” under Google In the right hand pane, then select remove. Once you select remove, it will ask if you want to remove all data from the account. Select>Okay. 

3. Close system preferences

4. Open Mail. Choose Mail>Add Account and select Google Mail and continue. 

5. Once Gmail is installed in Apple mail, sign into Google and add the accounts back onto your MacBook.

This has happened to me twice. I found a solution that works and hope I remember it next time. The problem is an authentication issue - for some reason Apple randomly flags the gmail password as expired and denies access. This can be fixed in keychain - search in keychain for gmail or your gmail account. One of the search results will contain the word "expiry". Delete that line and you are back in business - you will be able to re-add the account with no authentication issue if you had deleted it in mail.

GMAIL problems and account in general go on and OFF after updating Mac OS Mojave.

Resolved: DISABLE SOCKS Proxy because it can turning on by itself.

Mac OS devices running Mojave (any version): 

• SOCKS proxy is automatically re-enabled after every reboot/power cycle. 

By default, no proxy settings should be configured. 

The proxy is configured with: localhost port 8080

This causes all email apps to go offline intermittently.

Also it causes all web browsers to become "unable to load" any web page and this is why GMAIL can't authenticate the accounts even when you try to delete or add the account.

Once the proxy is manually disabled in Network Preferences; everything works fine. 

Recheck SOCKS Proxy in case of problem.

I have the answer... here is what I did and got it to work.

1.- remove the keys and certificates from the keystore (under Launchpad/Other/KeyChain Access), search for google and remove them all

2.- remove the two step verification with my cellphone... (Google Security under accounts) not sure if needed, but i wanted it to be straight forward

3.- Removed the Google account under the (System Preferences/Internet Account) on the Mac

4.- Removed access to MacOS (Google account/Security/Third-party apps with account access)

5.- Reboot, just to be clean...

6.- go to System Preferences/Internet Account/ add google account.

That seemed to have worked for me after sooooooo many weeks of trying, i am in..!

please let me know if this helps you.

I have wrestled with this problem since 26 March, the day I upgraded my system to 10.14.4. Apple didn't fix it in the next upgrade either. The workaround I am using, which was published in this forum weeks ago is: deactivate (not delete) the gmail account that is affected. proceed through the steps to establish a new gmail account. In my case the new account works just like the old one did before the authentication problem began. I suggested not deleting the old gmail account just in case, some day, Apple does its job and gives us a fix. At that time, we can decide whether to continue with the newly established account or apply the fix to the old gmail account and use it as before. Good luck!