Thunderbird 커뮤니티 포럼

How do I access my e-mail account;jrltique@goldrush.com? I have had this for many years and just got a new computer and am totally lost! I always logged onto Mozilla \thunderbird!

I am assisting an elderly user with a personal @hotmail.com account that receives email successfully in Thunderbird but cannot send. I have confirmed they can send and receive emails from their online outlook.com portal. The user's computer setup is as follows:

• Windows 11 (with latest updates).
• Thunderbird 153.0.2 (64-bit).
• A personal @hotmail.com account with the following server configurations:

  -> Incoming IMAP: outlook.office365.com, port 993, SSL/TLS, OAuth2, and
  -> Outgoing SMTP: smtp-mail.outlook.com, port 587, STARTTLS, OAuth2.

Thunderbird successfully authenticates to Microsoft using OAuth2 for incoming email. However, when Thunderbird attempts outgoing email authentication, Microsoft's SMTP server rejects the authentication. The Error Console in Thunderbird records this message: "535 5.7.139 Authentication unsuccessful, SmtpClientAuthentication is disabled for the Mailbox."

-> Refer to attached image: "Thunderbird Error Console_20260811.jpg". -> I am able to provide a short screen recording demonstrating the failure if needed.

To try and resolve the above, I completed the following actions:

1. Confirmed Thunderbird is current (153.0.2).
2. Confirmed SMTP is configured for OAuth2 rather than Normal Password.
3. Confirmed port 587 and STARTTLS.
4. Re-authorised the Microsoft account/OAuth connection.
5. Confirmed IMAP OAuth2 works.
6. Confirmed Outlook.com webmail can send successfully.
7. Reviewed Mozilla's current “Microsoft OAuth Authentication and Thunderbird in 2026” guidance, including the section covering cases where IMAP/POP works but SMTP does not.
8. Captured the SMTP failure in Thunderbird's Error Console.

However nothing worked, so I raised the matter with Microsoft support and eventually had the matter referred to their Tier 2 team. The Microsoft case number is: 7107041963.

Microsoft Support confirmed that for a personal Outlook.com/Hotmail account there is no user-accessible mailbox-level SMTP AUTH setting, and advised that SMTP is enabled by default for supported clients. However, because sending from Outlook.com webmail works, Microsoft Tier 2 declined to investigate the SMTP server response further and directed me to Thunderbird support.

I am able to provide a copy of the chat transcript if needed.

In any event, the TLDR version IMAP works using OAuth2, but SMTP using OAuth2 fails because Microsoft's SMTP server reports SmtpClientAuthentication is disabled for the Mailbox. Microsoft Tier 2 has referred the issue to Thunderbird support.

Questions:

1. Is this a known current issue affecting personal Outlook.com/Hotmail accounts using Thunderbird?
2. Is 535 5.7.139 SmtpClientAuthentication is disabled for the Mailbox known to occur with Thunderbird OAuth2 even though IMAP OAuth2 succeeds?
3. Is there a current Thunderbird-side workaround or alternative SMTP server/configuration recommended for personal Hotmail accounts?
4. Would changing the SMTP server from smtp-mail.outlook.com to smtp.office365.com be appropriate for a personal Hotmail account in Thunderbird 153, or should the current Microsoft-documented server be retained?

-> I note there appears to be conflicting advice on this point in previous support threads.

1. Given that IMAP OAuth2 authentication succeeds for the same Microsoft account, does this indicate that Thunderbird's Microsoft OAuth authorisation itself is functioning correctly, or could SMTP require a separate permission/token that may be failing?
2. Are there any additional Thunderbird logs or diagnostics I can provide that would help resolve this matter?

Disclosure: I used ChatGPT to help organise my troubleshooting notes and technical details for this post. The troubleshooting, observations and diagnostic information described above are from my own work on the affected PC.

My Thunderbird was working fine today, all messages received, could send/receive email and all parts of my profile that I had set up (ie custom archive folders) were present and had emails.. I did a Windows update and when I reopened Thunderbird there was a pop up prompting me to login to my yahoo email. I did so and now everything is gone, all folders are empty - no emails and none of the unique folders I had created. The only thing that I can tell is still present is my address book. I am also unable to send or receive emails. When I try to send an email (to myself or anyone else) I get a pop-up "The mail server responded: Request failed; Mailbox unavailable. Please verify that your email address is correct in your account settings." I checked and the email listed is correct, the one I have been using my entire life. I also checked my Server Settings and they appear to be correct. (I have a cox.net email address which I transitioned to yahoo several years ago as instructed by Cox, as Cox no longer supports email - everything has been working perfectly until today) I also see there was a Thunderbird update done at 5:53PM today which would have been the same time I did the windows update (Thunderbird 153.0.3esr). I sent an email to myself from my yahoo website email and it never arrived in my Thunderbird Inbox but it DOES show in my Thunderbird "Sent" folder. I do have a Thunderbird backup ZIP file but unfortunately it is about a year old so obviously won't have some stuff I would not like to lose. Thoughts?????

I tried the instructions at https://support.mozilla.org/en-US/kb/moving-thunderbird-data-to-a-new-computer, and watched the video. Copied and pasted exactly as instructed - nothing happened. Is it possible to transfer the data, including message filters and in-box folders, to the new PC? Old PC: version 115.18.0 esr (32-bit) - on Windows 7 New PC: version 153.0.3 (64-bit) - on Windows 11 Or is this data transfer impossible due to incompatibility of the different Thunderbird versions? Thanks. I also tried transferring the data from the old PC to a slightly newer laptop on Windows 10, utilising Thunderbird version 140.13.0 esr (32-bit). Nothing happened there either. Is it a lost cause? Do I just go ahead and create new message filters on the new PC and forget about trying to transfer the data and associated rules? Maybe that's the way to go for me. Thanks.

I have had Thunderbird from the time I acquired my Mac computer. This week it started to do something new. After a restart I opened Thunderbird. A box came up that says across the top System Integration. The cursor balloons, and hasn't stopped for the time I powered the computer, as least fifteen minutes. You know how the program icons are in a dock across the bottom. With other browsers open, hitting the Thunderbird icon doesn't bring its window into the forefront. This needs either a reset, or possibly a backup first. Is there a quicker way to fix this? Thanks in advance. I am not using a VPN; but I also have Thunderbird on my Windows 11. You might have seen a more recent thread on that installation. I included a screenshot. It was easier here to do that than on the Windows 11. On the Mac, I just had to use Activity Monitor to close out of Thunderbird in order to get its version.

In Thunderbird, how can I stop text in the previous emails in a string turning blue?

I have looked everywhere in Settings where colour is mentioned and everything is set to black text on a white background. Nothing is set to blue.

I do not want to see blue text anywhere.

Please advise.

I installed thunderbird for Windows on PC all was good till it went looking for a outgoing server a red box popped up and said outgoing server is already installed . That ended the install.

Thunderbird just updated and the next time I opened it all of the folders I created and the emails I'm storing within them are missing. I found my profile as directed. I'm not sure if I have a backup of it. I've included the screenshot as you ask for. I know that those folders and emails are there as I was playing around with the the 3 lines > View and when I moved between the different choices I saw my folders/emails are all in there.

Any assistance you can provide is appreciated!

When I up dated the latest version of T.B.. when switching form the index desk top page to read the email, the page is blank EXCEPT for "SWITCH TO: EXTENSION" displayed at the top of the page

The T.B. icon is not is not displayed

I have been using the INBOX that is under my email address. This worked for years except one time before when the same thing happened where the messages are from years ago. I have to go further down to use ALLMAIL to get the current messages. The INBOX shows "3" while the ALLMAIL shows 5,626.

So, the INPUT is not current as before but old messages. How do I fix this?

Thanks,

Eddie

I was a satisfied user of the Thunderbird e-mail client. I especially enjoyed the ability to toggle into darkmode when browsing and reading my e-mail. The previous toggle I used to activate that feature is missing, and I cannot locate a work around to turn it back on. Any assistance would be greatly appreciated. Thanks

Im looking for help to set up my Hotmail account. I have 4 emails. They all worked perfectly for a long time. All of a sudden, everything just stopped. I have tried everything and the configuration seems to be correct. Ive tried every fix i could find. It just no longer makes sense to me. Does it just not work with Thunderbird? The specific message is "User is authenticated but not connected". Also when i tried to send an email, i get "Login to server smtp-mail.outlook.com with username **********@hotmail.com failed."

I have installed Thunderbird to work with my spectrum email account. I had successfully installed it and was even able to recieve emails, but could not sent them. I uninstalled it, reinstalled it and now I can't receive emaill either. The settings for the servers and my username (fulll email address) all look correct per spectrum's website. Whenever I enter my password into Thunderbird I get:

"Login to server mobile.charter.net with username stynee@ca.rr.com failed."

Next steps?

My email account [redacted from public] @live.co.uk was receiving mail until 6th August and then nothing. I'm getting a notification to say authentication failed and when I tap it the screen says "checking incoming server settings" and doesn't complete. I'm in the process of changing Web account logins from a talktalk account to the live account as the TT account is attracting spam. Could this have influenced the server settings?

Richard

After the most recent update to Thunderbird, I can no longer copy attached files on incoming emails to either my Quickbooks program or a folder on the hard drive by dragging over. Now must copy manually to drive. Can this be corrected?

Hi, I have two accounts in my Thunderbird. They are Gmail (regular gmail account) and CFCC (an institutional account). The CFCC shows up in my Unified Folder list but the Gmail does not. Is that normal? The main Inbox is showing all incoming emails from both accounts so no performance issues, just wondering how to get rid of the CFCC (if that's possible) to eliminate clutter. Thank you. GES

Coming from https://support.mozilla.org/en-US/kb/cannot-send-messages, and https://support.mozilla.org/en-US/questions/1596545#answer-1837376 (thank you christ1)

Account settings attached. I don't have an active firewall. My email provider is microsoft (outlook) No antivirus installed Linux Mint 22.3 x86_64 Thunderbird 153.0esr

I have confirmed with microsoft support that the ports and such are correct, they claim thunderbird is the problem.