Mail and Google's OAuth 2.0 policy

I had the same problem and I tried a lot of methods. The only one that worked was to upgrade High Sierra to Catalina 10.15.7

We may be driven to a newer Mac or using WebMail only.

Answer for Mail and Calendar is here: Calendar and Google's OAuth 2.0 policy - Apple Community

I had the trouble on high Sierra ,

I found a method with app password and double authentication (password proposed by google , and only 16 bytes size)

in emergency I adopted this method

before my password were 4 times longer

I consider that I have to choose the password , and only me have to know it

in operating systems the administrator doesn't know password of users , he doesn't propose any one

after I upgraded to Mojave

can I put longer password ?

perhaps to fallback on method "se connecter" if mail is oauth2

double authentication is not my preferred method , I prefer a very stronger password

my question is

what level of mail/Mac OS X is compatible with oauth2 of google ?

I had the same problem and i spent two days to find the solution.

But finally it worked.

You just need to update your macOS to Catalina and restart your Mac.

I tried multiple fixes since I experienced the same issue. Only upgrading High Sierra to Catalina 10.15.7 was successful.

I'm in exactly the same situation. I think we're stuck using webmail until we replace the computer.

Hi Scoop8! I'm having the exact same problem! I have a Mid 2011 iMac running High Sierra 10.13.6 and Mail v11.5, and cannot access my Gmail account through the Mail app any longer. Every time I try to add it, I am getting the same Error message as you. I hope the app developer you contacted upgrades the Mail app so we can use it again. I can't afford a new iMac, so, like you High Sierra 10.13.6 is as high as I can go. For now, like you, I'm having to use webmail and I really don't like it at all. Thanks for clearing up this for me as it was making me crazy!

Apple announced it would stop supporting High Sierra as of Sep 2020. Speaking as a High Sierra user myself, I don't blame them for doing what they said they'd do...we've had plenty of notice. Looks like it's time to put the old girl out to pasture.

Any Mac that can do 10.12.3 can do 10.13.6

 Start up from macOS Recovery

Option-⌘-R

Upgrade to the latest macOS compatible with your Mac.

APFS won't work for Sierra, Sierra needs MacOS Extended Journaled. High Sierra won't work for APFS on earlier Macs.

What has often worked for others is to use this Restore Method instead of CMD+r keys...

Option-⌘-R

Upgrade to the latest macOS compatible with your Mac.

2017 iMac failing to install Sierra in re… - Apple Community

Clean Install of High Sierra: Multiple Fa… - Apple Community

Sorry, my last post was assuming that your Google login is a gmail address. In your case, you need to specify respectively Google’s IMAP and SMTP servers, i.e. if I’m not mistaken imap.gmail.com and smtp.gmail.com

Currently on Big Sur and Apple's Mail still does not support oauth2.

I'm running Big Sur on a Mac Mini Late 2012 using Open Core Legacy Patcher. Big Sur is the end of the line supporting the ivy-bridge motherboard, and I don't have the money to buy a newer computer.

I don't want to use IMAP but POP, because I want to delete mails from the server as soon as I download them to my computer. I don't want to share my email on different devices.

I cannot use Google 2-factor authentication and generate an App Password, because it requires me to give Google my phone number, which is not going to happen. Hence, I'm stuck with Mozilla Thunderbird, which is not as nice as Apple Mail.

So please, Apple, please have mercy and give us oauth2 and a patch for older mail clients.

Having EXACTLY the same problem on a 2010 iMac with same OS (10.13.6).

PLEASE help!

gmail on mail Version 11.5 (3445.9.1) - Apple Community