OAuth2 desktop apps Thunderbird & Mailspring fail AADSTS90302 on Outlook.com
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Cael
5
Reputation points
I've been trying to switch to a mail app where I can manage all my emails in one place. Everything adds fine - including gmail and hotmail - but no matter what, I can't get my outlook account (this account) to work on ThunderBird. It's even worse on MailSpring: hotmail doesn't work.
No matter what I've tried and how much troubleshooting, I just can't get it to authenticate. I've changed my password, I've tried generating app passwords, and I can reliably log in on the web.
Brand new version of both programs used, on W11 though this OS is irrelevant.
What is going on? I'm hoping this can be fixed. Thanks.
Windows for home | Windows 11 | Apps
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YvanM 0 Reputation points2026-01-23T01:27:25.0033333+00:00 As of today I have the same problem with Thunderbird on Android and on Linux..everything was working well yesterday using 0Auth2. I even tried a new Thunderbird install on Linux (Flatpack): it worked once and failed as soon as I closed and restarted the app.
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YvanM 0 Reputation points
2026-01-23T01:38:36.25+00:00 FYI, it looks like it might have been a transient problem server side as it just started working for me on both my Android phone and my Linux computer.
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