topic Re: Thunderbird and Outlook SMTP in Discussions

Thunderbird and Outlook SMTP

thesamim — Tue, 08 Aug 2023 21:28:27 GMT

Version: 115.1.0 (64-bit) (tried with 114 as well.)

Set up an account that's based in outlook.live.com. Receiving emails just fine. Getting all folders.

Note: it's annoying AF that you have to restart TBird every time you make a smtp change!

Can't send emails. Authentication methods tried:

normal password	Login to server smtp.office365.com with username sami@... failed
Encryption password	The Outgoing server (SMTP) smtp.office365.com does not seem to support encrypted passwords. If you just set up the account, try changing the 'Authentication method' in 'Account settings \| Outgoing server (SMTP)' to 'Normal password'.
Kerberos	ditto
NTLM	ditto
oAuth2	Login to server smtp.office365.com with username sami@... failed. NOTE: I see no evidence that it tried to get a token.

Re: Thunderbird and Outlook SMTP

termite728 — Fri, 15 Sep 2023 02:58:09 GMT

in my case,

Thunderbird A migrated to current upgrade with some hassles with Microsoft concerning access. In that instance Tools-AccoutSettings SMTP Oauth2

Thunderbird B migrated to current upgrade with persistent failures. I removed saved login/password entries. No success. I then modified Tools-AccoutSettings SMTP Normal Password Success was had.

Both A & B function with the different setting between them. The specific accounts are all @outlook.com

Termite728

Re: Thunderbird and Outlook SMTP

thesamim — Fri, 15 Sep 2023 17:14:12 GMT

Tried all that. No success.

In debugger, looking at the network traffic:

When I use oAuth2, I can see the request for the token being made, a valid response is received. Then nothing.

When I use normal password: I see no requests going out.

Re: Thunderbird and Outlook SMTP

startherese — Sat, 07 Oct 2023 15:13:35 GMT

WHEN will TBIRD catch up with the rest of the industry and create a permanent fix for authentication using exchange server settings? This needs to be solved - period. I'm a small business owner and my web/email hosting has completely stopped using pop and smtp server settings. So after using Tbird for 25 years, I'm scre*ed. TBIRD needs to be the one to change - stop passing the buck. Using the browser and microsoft email programs is a time-wasting nightmare. PLEASE FIX THIS!!

Re: Thunderbird and Outlook SMTP

rolandog — Wed, 18 Oct 2023 08:07:56 GMT

Thunderbird can't issue a fix for something that Microsoft ~~broke~~ disabled by default:

Re: Thunderbird and Outlook SMTP

pettys — Tue, 05 Mar 2024 15:37:53 GMT

After much trouble, I found I had to enable SMTP AUTH at both the domain level AND the mailbox level. I used the instructions here:

https://learn.microsoft.com/en-us/exchange/clients-and-mobile-in-exchange-online/authenticated-client-smtp-submission

I did both the `Set-TransportConfig` and the `Set-CASMailbox` in order to get it to work.

Re: Thunderbird and Outlook SMTP

blued — Sat, 04 May 2024 08:34:14 GMT

Too many hoops and barrels to jump through to resolve this. Started using Windows Live Mail and works right out of the box. Goodbye thunderbird, been nice knowing you.

Re: Thunderbird and Outlook SMTP

termite728 — Sat, 04 May 2024 16:04:21 GMT

Termite728; Over a 6-week interval, the problem diminished and ceased on the problem machine. All is well at this point with Thunderbird across my units servicing multiple outlook accounts on each. In my opinion the mail provider is the primary suspect.

Re: Thunderbird and Outlook SMTP

Flaco74 — Thu, 18 Jul 2024 15:10:03 GMT

Had troubles with Thunderbird Nebula. I deleted all SMTP settings. And then, sending emails worked fine for me. Went to Tools> Account settings > SMTP Settings (bottom of accounts), and then deleted all SMTP accounts associated with a hotmail/outlook account. Not sure how this did it, but I can send emails out now. Hope this helps.

Re: Thunderbird and Outlook SMTP

Flaco74 — Thu, 18 Jul 2024 15:18:48 GMT

I am using an app password from Outlook, and 2F Authentication to log in to IMAP server.

Re: Thunderbird and Outlook SMTP

ET122 — Sat, 03 Aug 2024 16:53:55 GMT

I like Thunderbird's ability to connect to multiple email accounts as I have such multiple accounts for different purposes.

However, fiddling with the outlook.com SMTP server settings was a nightmare even if I usually managed to find something that eventually worked (until the next time). Today, based on your instruction of deleting all SMTP accounts associated with my outlook account, I managed to get send-mail to "work with outlook.com" by selecting "Use Default Server" as the SMTP server. For me, this default SMTP server defined by Thunderbird seems to be the Gmail SMTP server. Seems to work. The sent email ends up in the Sent folder of my outlook.com account and it has my outlook.com email address in the headers.

Re: Thunderbird and Outlook SMTP

ET122 — Sun, 11 Aug 2024 14:47:53 GMT

Correction: That workaround using the Gmail SMTP server causes the email to be sent from my Gmail account.

I did find that Thunderbird does seem to set up the correct outlook.com settings (IMAP and SMTP) if, after deleting the outlook.com mail account from Thunderbird, I reboot Windows before adding the account back in.

Re: Thunderbird and Outlook SMTP

Flaco74 — Tue, 13 Aug 2024 16:18:17 GMT

I was having issues with password apps again. I cleared all password apps from my outlook account, and generated a new one and entered it into Thunderbird. Now things are working as desired. I may have had more than 40 app passwords, and that was creating an issue.

Re: Thunderbird and Outlook SMTP

Stelzi79 — Wed, 21 Aug 2024 19:09:04 GMT

So basically my somewhat silly and persistent issues of Firefox not properly working with Outlook stems from the fact that the Firefox team "forgot" to properly migrate or properly inform everybody that Firefox refuses to do ALL (receiving and sending) necessary migration steps.

Considering that this thread was started about ONE YEAR AGO ...

At this point I wish for the times back when somebody could purchase an email client for the desktop! At least at these times there was a small chance the coders of that client cared just a little more for their customers.

But who am I - just an old man that is angry at the clouds!

Re: Thunderbird and Outlook SMTP

user9 — Wed, 18 Sep 2024 16:10:37 GMT

I had switched to MS Outlook client because SMTP via OAuth2 was not working for a while on my personal Outlook account. However, today I was able to fix the issue and get back to Thunderbird. I don't know if it will work for others, but here is the solution I used:

1. Configured my Outlook account with OAuth2 in Thunderbird as usual.
2. Tried to send an email, but it didn't work.
3. Created a second email address in my Microsoft account settings.
4. Replaced my existing email address in Thunderbird's SMTP settings with the second email address in the user name.
5. Tried to send an email again, and a new authentication window popped up. Then I authenticated again.
6. Now I can send emails as before.

Re: Thunderbird and Outlook SMTP

neverwinter — Tue, 23 Sep 2025 15:11:54 GMT

Yes! I can confirm this workaround still works. I have entered my another mail (actually, an alias of the same email), an OAuth window popped up, I logged in, IT DIDN'T WORK then. Then I reverted to the original email in the SMTP settings, it didn't request any authentication and just started working.

Re: Thunderbird and Outlook SMTP

settling — Thu, 05 Mar 2026 15:12:04 GMT

As of 2026, it is only this workaround that worked, setting to a wrong/non main alias using smtp-mail.outlook.com starttls and oauth, then trying to send a mail. Authenticate via oauth, but will not send as the alias is not the right account. Then switch smtp server setting back to main/login address, resend and let oauth double check some popups and voila. Why is there not just a force reauth for Oauth or something. This is so bad. Without this post I would have never managed to get it working.

Re: Thunderbird and Outlook SMTP

aj2 — Thu, 12 Mar 2026 23:08:17 GMT

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