Thunderbird 社区论坛

Can not send emails to a newly created outlook.com (free) account. Have tried dozens of different settings, approaches.

My current setup:

 - windows 10
 - thunderbird 140.8.0esr (64-bit),  numerous previous versions also do not work
 - outlook.com (free) account mail provider
 - POP3 enabled (tried IMAP enabling also) on outlook.com account
 - no 2FA or 2FA enabled on outlook.com account, no difference
 - outlook.com web access works fine
 - followed instructions in mozilla support article Microsoft OAuth Authentication and Thunderbird in 2024 
      (https://support.mozilla.org/en-US/kb/microsoft-oauth-authentication-and-thunderbird-202)
 - have done a fresh install on a new machine without an existing profile.
 - have tried various microsoft servers, have tried oauth2, normal password
 - thunderbird account creation works just fine.
 - server settings and SMTP settings match as recommended by support article noted above
    SMTP server settings
        server name: smtp-mail.outlook.com  
        port: 587
        connection: STARTTLS
        authentication: OAUTH2
        user:  xxxxxxxx@outlook.com

symptoms:

 - receiving(downloading) emails works fine.
 - sending emails fails with following messages
     Login to server smtp-mail.outlook.com with username  xxxxxx@outlook.com    failed    followed by 
           Unable to authenticate to Outgoing server (SMTP) . Please check the password and verify the 
             'Authentication method' in 'Account Settings | Outgoing server (SMTP)'

Many people seem to be having this issue with no resolution.

Please help.

When I go into my email program it asks for a password over and over again. it doesn't matter what password I put in, nothing works. Thunderbird has tried to send codes, but they don't go through to my email program. I have used my iPad with a different email address to check some things and go to Shaw Webmail to retrieve my emails. I need it to work as I have lots of files on there that I use often with a volunteer organization among others.

I have never deleted so many emails at one time, around 500. Did I exceed the limits of Thunderbird? I cannot log on. Cannot see new emails. I have been on emailsrvr.com and did verify my passwords. Thank You

Hi I keep getting the message "Unable to connect to your IMAP server". I have reduced the number of 'server connections to cache' from the default 5 down to 1. Thanks

I can receive mail fine. Cannot send mail on gmx.co.uk acct, but gmx.net works on oauth2. But oauth2 is missing on gmx.co.uk It's just not on the pulldown. I tried a new thunderbird acct for gmx.co.uk but oauth2 is still missing.

Can get(POP3), but can not send emails to a newly created personal outlook.com account.

the following error occurs when trying to send mail: Unable to authenticate to Outgoing server (SMTP) . Please check the password and verify the 'Authentication method' in 'Account Settings | Outgoing server (SMTP)

all my setting are correct per thunderbird and microsoft:

  (smtp-mail.outlook.com, port 587,  STARTTLS, OAUTH2, xxxxx@outlook.com)

thunderbird error log file contains the following: . . . mailnews.smtp: S: 535 5.7.139 Authentication unsuccessful, SmtpClientAuthentication is disabled for the Mailbox. Visit https://aka.ms/smtp_auth_disabled for more information. [CH5P220CA0005.NAMP220.PROD.OUTLOOK.COM 2026-02-28T23:29:21.878Z 08DE7703D4D1982A]

SmtpClient.sys.mjs:452:17 mailnews.smtp: Command failed: 535 Authentication unsuccessful, SmtpClientAuthentication is disabled for the Mailbox. Visit https://aka.ms/smtp_auth_disabled for more information. [CH5P220CA0005.NAMP220.PROD.OUTLOOK.COM 2026-02-28T23:29:21.878Z 08DE7703D4D1982A]; currentAction=_actionAUTH_XOAUTH2 SmtpClient.sys.mjs:578:19 mailnews.smtp: Error during AUTH XOAUTH2, sending empty response . . .

Based on my understanding its seems thunderbird is using SMTP AUTH instead of OAUTH2 as required for newer personal outlook.com accounts. Is my assessment correct? If so, is there a fix?

I've checked and double check as well has changed the outgoing settings from 465 to 587. Nothing works. Help148.0 Sending of the message failed. An error occurred while sending mail: Outgoing server (SMTP) error. The server responded: resomta-h2p-555627.sys.comcast.net resomta-h2p-555627.sys.comcast.net Excessive failed authentication, ESMTP server temporarily not available.

Doesn't matter if I click File -> Get All New Messages or press Shift + F5 nothing happens and I don't get emails. Have to check each email account one by one. Downgrading all the way to version 78 didn't help. What can be wrong?

Also I've tried installing a special add-on to get all new message: https://addons.thunderbird.net/en-US/thunderbird/addon/get-all-mail-button-for-tb78. But it's not working either. Just nothing happens when I press the button provided by the add-on.

I am trying to connect to usenet via my news.newshosting.com account. I can read the newsgroups ok but cannot send a reply for some reason. I get "user posting not allowed" followed by " Sending of the message failed. The message could not be posted because connecting to the news server failed. The server may be unavailable or is refusing connections. Please verify that your news server settings are correct and try again."

Continuation of my prior post: https://support.mozilla.org/en-US/questions/1516342

Thunderbird has a routine problem with being unable to log into various mail servers. I have four accounts and they all seem to share this problem.

Most recent update: I've tested this in Windows Safe Mode, and the problem has not appeared. Since I can't do any useful work in Safe Mode, it's hard to give it a thorough test, but so far so good. Also, I have removed AVG antivirus because it was redundant. I have seen no improvement since it was removed.

Can this problem be resolved?

I am setting up Thunderbird on a Win10 machine, and am having a lot of trouble adding accounts that I did not have on the two Win11 machines I have set the same accounts up on.

When adding my 2 GMail accounts, after clicking "Allow" on the OAuth popup the button would go grey the window would stay open and not close, and the account would not be added.

Changing the general.useragent.compatMode.firefox option to TRUE allowed me to progress and finally add those accounts.

I am now having the same trouble with my @hotmail.com account. When I add the account, the dark blue OAuth window pops up, but is completely empty, and there is nothing more I can do.

Things I have tried

• Reverting the above config change
• Checking that cookies and JavaScript are enabled
• Checking there is no saved password
• Used both the Account Hub and the default dialog, with the same effect.

Thanks in advance!

My 140 version of Thunderbird froze and I removed it and downloaded 140 afresh but it will not run. I just get a white screen and the settings button will not respond.

I cant receive emails only send them. I receive an error message when starting Thunderbird "the current operation on inbox <my email address> did not succeed"

Hello Team,

Perhaps you can help?

I have used "T Bird" for years, lately I've loaded it on another pc to access my mail and all the filters don't work, no log being written and no folders being filtered! Windows 10,Thunderbird 147.0.2

Any pointers?