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Thunderbird 115.0.1 - Cannot send/reply email from my personal (not corporate) Outlook account - SOLVED by setting account "Normal password" instead of Oauth2

  • 9 replies
  • 7 have this problem
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  • Last reply by Toni

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I was able to send emails till July 14. After that day it's been impossible to send or reply to messages from my Outlook account (I receive emails though). I have made no changes to Thunderbird's configuration since then. Basically it's the Oauth2 authentication that fails. I briefly see a browser page for authentication, wait, wait, wait and then the mail is not sent and I get an error message related to servers timeout (attached). Sorry, my interface is in Italian, but anyway the message is something like: "Unable to send email because of a timeout on the connection to the out server (SMTP) smtp.office365.com. Try again." Is this a known bug? Any ideas? It's quite annoying to use the browser interface to send messages while I am able to receive them in Thunderbird :) Thank you in advance, guys!

I was able to send emails till July 14. After that day it's been impossible to send or reply to messages from my Outlook account (I receive emails though). I have made no changes to Thunderbird's configuration since then. Basically it's the Oauth2 authentication that fails. I briefly see a browser page for authentication, wait, wait, wait and then the mail is not sent and I get an error message related to servers timeout (attached). Sorry, my interface is in Italian, but anyway the message is something like: "Unable to send email because of a timeout on the connection to the out server (SMTP) smtp.office365.com. Try again." Is this a known bug? Any ideas? It's quite annoying to use the browser interface to send messages while I am able to receive them in Thunderbird :) Thank you in advance, guys!
Attached screenshots

Modified by Wayne Mery

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Thank you @sfhowes, I have already checked the antivirus settings, and Thunderbird has both incoming and outgoing traffic allowed and trusted. The TBird settings are all ok also. I don't understand why before July 14th I was able to send and receive seamlessly, and now I can't any longer. I also checked OS updates, but hadn't any after that date. Tried deleting saved passwords in TBIRD, but no change. If I set "Normal password" instead of Oauth2, I can send emails. So the issue is with that protocol. It sounds weird to me that I am the only one with this issue :) even if I know that there is the same issue for corporate emails (that is not my case, because my Outlook account is personal).

sob:
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Hi there simona We have read the message We are trying to help The server reporting a server timeout. means that you temporarily cannot use this connection within 30 seconds and sometimes a little longer. sometimes your connection suddenly reappears. To be able to solve these if it takes longer. can you try checking your settings to continue. It could be your browser, internet connection, website server, firewall or browser.


for the connection to the oauth2 connection. checks that you have entered the correct e-mail address. Also check whether you have correctly set the cookies that are required for this.


Greetings firefox volunteer.

Modified by Googlethunderbird

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Hello there


-The next steps you could check or go to are:

-check your internet connection.

-clear your browser data

-change the Dns settings.

-flush Dns and change the settings of your Ip.

-Update Your Computer's Network Adapter Drivers.

sometimes your connection suddenly reappears.


Greetings Firefox volunteer

Modified by Googlethunderbird

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Hi volunteer, I'm sorry but I have already checked the reasonable stuff. Checking internet connection, and flush DNS? :D The issue is with Oauth2 autentication, that just doesn't work. I don't need the usual general advices you wrote above, that don't refer to this issue, and honestly sound to me like a pre-made answer :) I usually avoid processed food as well as processed answers - I hope you understand I'm kidding, but there is some truth in what I wrote.

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Hello there

OK, I received your message. Yes, you're kidding, we're with Thunderbird, you can.


Greetings Firefox volunteer.

Modified by Googlethunderbird

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What's the antivirus? If you have the correct settings, i.e. smtp.office365.com on 587, STARTTLS, OAuth2, email address, the antivirus is a common cause of timeouts and blocking the connection to the OAuth2 authentication site. Especially if it's a non-Windows Security app like Avast/AVG, Norton etc.

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Chosen Solution

Thank you @sfhowes, I have already checked the antivirus settings, and Thunderbird has both incoming and outgoing traffic allowed and trusted. The TBird settings are all ok also. I don't understand why before July 14th I was able to send and receive seamlessly, and now I can't any longer. I also checked OS updates, but hadn't any after that date. Tried deleting saved passwords in TBIRD, but no change. If I set "Normal password" instead of Oauth2, I can send emails. So the issue is with that protocol. It sounds weird to me that I am the only one with this issue :) even if I know that there is the same issue for corporate emails (that is not my case, because my Outlook account is personal).

sob:
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Hi Simona

"If I set "Normal password" instead of Oauth2, I can send emails. So the issue is with that protocol." ^^^^ That indicates to me that it's a problem on Microsoft's side (and/or Antivirus is changing things silently). We have many of these issues reported and there's no consistent pattern as I am sure our ace volunteer sfhowes would agree!

  • Some people fix it by changing to "Normal password"
  • Some people manage to get Oauth working (there is a Thunderbird "papercut" bug where if your outlook/hotmail/live.com/Microsoft365 is set to Oauth and you fill in the password in Thunderbird instead of leaving it blank and then. click "Done", then Thunderbird skips opening Firefox to ask for the OAuth password and then fails to authenticate.

Anyway: All's well that ends well, glad you got it working! Closing this thread.

Cheers! ...Roland

Modified by Roland Tanglao

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Thanks for sharing your solution

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I tried the solution (setting it to Normal Password) and it made no difference. I can send just fine from my Gmail account, but not the Outlook and Live accounts. I am running Thunderbird 115.2.0 with Windows 10. My installation of Thunderbird was upgraded from 102 last night. I cannot seem to find an answer that works.