Thunderbird Community Forum

Hello all, I'm getting "Authentication Failure" popups, even though Thunderbird works fine, sending and receiving. I researched various sources and all deal with Server Settings. All email addresses are correct with passwords.

But here is something I noticed: In account settings, left pane, under Server Settings, - Connection Security is set to SSL/TLS and - Authentication Methos is set to OAuth2 ... as usually recommended for both

However, going to the main window in account settings (same account), scrolling to the bottom, under Outgoing Server > edit outgoing server > Connection Security is: STARTTLS ...???

Is this maybe the reason of Authentication Failure? (different from Connection Security under Server Settings.

Any thoughts on that? Should both be the same? Thanks for now

Hello, I’m trying to install Thunderbird email client for my IMAP domain and my POP domain. They are on the same server but different passwords. I don’t get a place to enter passwords. Why?

I am using the correct password but it keeps saying " Login to server imap.comcast.net with username [redacted]@comcast.net failed.". I hope someone can help. Thanks.

Authentication error. Show less

Component returned failure code: 0x80004005 (NS_ERROR_FAILURE) [nsIMsgAccountManager.createIncomingServer

I'm getting the above errorr. I cleared out my cache and still does not work. I did have trouble with accepting the setting and seem to get thru that part but authentication still not working.

153.5.1esr (64-bit) Release notes

That's the version I'm using and trying to authenticate to my gmail account. What is going on? Phillip

I was bumped off Google and Thunderbird for some reason but my wife's account was left alone. eM was recommended by a friend but I much prefer to get back on T-bird, can you help? Thank you very much.

Hi there the message shown in the attached image appears every time I open Thunderbird! I have to cancel it.

I have checked all the server settings in Thunderbird which are set to Oauth2. The servers connect without any problem. The email account in Thunderbird always works both sending and receiving.

Is there any way I can stop the very annoying pop up occurring?

Thanks for your help! Deryck

To ask this question, I had to sign in. But the password to sign in, which permits me to reach this page, where I can ask this question, does not give me access to my email. I have tried using my apple account password and my computer password to no avail. How do I fix this?

Hello,

I'm moving to Graph from EWS and have followed the instructions at: https://support.mozilla.org/en-US/kb/microsoft-ews-graph-migration

I get through to screen that offers Graph API as an option, alongside IMAP, POP3 etc, and click on Graph API which directs me to my browser to log in to my email service (via GoDaddy). I log in successfully which takes me to the Thunderbird 'You're All Set' screen saying the account has been securely connected to Thunderbird and therefore ok to close that screen.

Back on Thunderbird it then progresses but returns with "Authentication Error - unable to log in at server. Probably wrong configuration, username or password".

The username and password are correct, and there aren't any other options available when editing/manually configuring the connection...so at a dead end, alas.

Any pointers much appreciated!

• • Titel: Yahoo-Mail lässt sich in Thunderbird 153.5 unter macOS nicht anmelden – „Es ist ein Problem aufgetreten“**

Hallo zusammen,

ich kann mein Yahoo-Mail-Konto seit etwa zwei Wochen nicht mehr in Thunderbird einrichten. Ich vermute ein Problem mit der Yahoo-OAuth2-Anmeldung.

• • Mein System:**

- Betriebssystem: macOS auf einem MacBook Pro - Thunderbird-Version: 153.5 - Weitere E-Mail-Konten in Thunderbird: Gmail, WEB.DE, GMX und Host Europe. Diese funktionieren alle problemlos.

• • Fehlerbeschreibung:**

Wenn ich mein Yahoo-Konto hinzufügen möchte, öffnet sich das Yahoo-Anmeldefenster. Ich gebe meine vollständige Yahoo-E-Mail-Adresse und mein korrektes Passwort ein. Anschließend erscheint folgende Fehlermeldung:

„Es ist ein Problem aufgetreten. Wir konnten Sie nicht anmelden. Versuchen Sie es bitte auf einem anderen Gerät.“

Darunter befindet sich ein lila Button „Hilfe aufrufen“.

Die Anmeldung bei Yahoo funktioniert dagegen problemlos über Firefox auf demselben Mac mit demselben Passwort. Auch die Anmeldung über meinen Passkey auf dem iPhone funktioniert.

• • Bereits durchgeführte Maßnahmen:**

- Yahoo-Passwort geändert und die Anmeldung über Firefox erfolgreich getestet. - Zwei-Faktor-Authentifizierung bei Yahoo aktiviert. - Yahoo-Konto in Thunderbird gelöscht und mehrfach versucht, es neu einzurichten. - Authentifizierungsmethode für IMAP und SMTP überprüft: OAuth2. - Cookies und JavaScript in Thunderbird aktiviert. - Im Konfigurationseditor folgende Werte überprüft:

 - `mailnews.oauth.usePrivateBrowser = true`
 - `mailnews.oauth.useExternalBrowser = false`
 - `javascript.enabled = true`

- Ein Yahoo-App-Passwort erstellt und versucht, das Konto manuell mit „Passwort, normal“ einzurichten. Thunderbird öffnet trotzdem wieder das Yahoo-Anmeldefenster unter `autodiscover.yahoo.com`, wo dieselbe Fehlermeldung erscheint. - Alte Yahoo-Einträge aus dem Passwortspeicher entfernt. - Doppelte Yahoo-SMTP-Einträge gefunden und den veralteten Eintrag entfernt. - Thunderbird vollständig beendet und neu gestartet.

Nach dem Neustart erscheint teilweise sogar eine Passwortabfrage für `peterbeck127@yahoo.com`, obwohl das Yahoo-Konto nicht mehr in der Kontenliste vorhanden ist.

• • Meine Fragen:**

1. Ist ein bekannter Fehler bei der Yahoo-OAuth2-/PKCE-Anmeldung in Thunderbird 153.5 vorhanden? 2. Warum lehnt Yahoo die Anmeldung in Thunderbird ab, obwohl dieselben Zugangsdaten über Firefox funktionieren? 3. Wie kann ich eventuell verbliebene Yahoo-Anmeldeversuche oder Servereinträge vollständig entfernen, ohne mein Thunderbird-Profil und meine anderen E-Mail-Konten zu beschädigen? 4. Gibt es einen bekannten Workaround oder eine Korrektur für dieses Problem?

Ich möchte mein Yahoo-Konto wieder normal über IMAP und SMTP in Thunderbird verwenden können, ohne meine anderen Konten neu einrichten zu müssen.

Vielen Dank für eure Hilfe!

Have got a replacement computer, and downloaded the latest TBird (having used it with AOL) for years). Following initial set up procedure, TB detects correct settings for AOL and the "enter password" page opens from AOL succcessfully for authorisation. AOL requires 2 factor authorisation, and I use a phone code for this.

However the speed at which the code arrives from AOL has always varied quite a bit, and today it is taking almost a minute so the TB set up screen is timing out long before the code arrives. Cant go on retrying as I will get locked out of the account. No point in going for manual set up as the auto settings are correct, so the same problem is going to occur. I have three AOL e-mail addresses to set up! Is there a workaround of some sort for this - its terribly frustrating and the set up screen "connect your e-mail settings" timeout period does seem quite short if you have to wait for a 2FA phone code or e-mail code - any delay in the arrival of which is completely ouside your control . Dave

I am trying to add a new Outlook.com email account to Mozilla Thunderbird on Windows, using IMAP with OAuth2 authentication.

The account works correctly through Outlook.com webmail, but Thunderbird repeatedly fails to complete authentication.

I have tried the following:

1. Configured the account using IMAP with OAuth2 authentication.

2. Checked the incoming and outgoing server settings.

3. Attempted to add the account several times.

4. Checked the POP and IMAP settings in Outlook.com webmail.

5. Tried using a separate Thunderbird profile to investigate the problem.

Thunderbird does not successfully authenticate the account, preventing me from adding it.

I already have existing email accounts in Thunderbird, including an ntlworld.com account and a Hotmail account configured using POP.

My intention is to migrate my existing ntlworld.com emails and folders to the new Outlook.com account using IMAP.

Could someone please advise why OAuth2 authentication is failing and what settings or troubleshooting steps are required to resolve this?

I would particularly appreciate guidance that will not interfere with my existing Thunderbird accounts or stored emails.

I have read the topic "Microsoft EWS to Graph Migration October 2026". I have followed the instructions meticulously MULTIPLE TIMES. Unfortunately for me, it DOES NOT WORK!! After deleting the EWS account, I proceed to create the new Graph account, but it fails (has failed) EACH AND EVERY TIME I've tried it. I finally had to give up, and restore/re-install/setup the Thunderbird EWS version. The failure reported on each failure was an "authentication failure".

My OS is macOS Tahoe 26.7.1; My Thunderbird version is 158.0. This is distressing! If there is an issue, I would expect T'bird to belay the update until the issues were fixed. If there is a "trick" required, I would appreciate someone sharing it with me. I'm aware that the causes of these issues is "Microsoft Incompetence", but AFAIK incompetence is not "contagious" - I don't understand T'bird/Mozilla releasing a fix with detailed procedures without testing.

EDIT: One other piece of information that may or may not be useful. The article "Microsoft EWS to Graph Migration October 2026" mentions a "Microsoft 365/Exchange Online email account". My account is an "Exchange Server" account; the Exchange server is hosted by Microsoft.

Thanks for any advice.

Best Regards, ~JM

Since Friday I have not been able to use thunderbird. I can open it but it wont connect to Virgin.com I have checked all settings (click on test connection it states good) then every five minutes when it try's to connect I get the following message (email address removed)

Login to server pop3.virginmedia.com with username ******* failed

I still get mail on my phone so it's down to a Thunderbird issue I believe. Tried to reinstall same issue, tried a new account and wont allow me to authenticate.

PLEASE can someone help - have a load of work to do but can't get on. Thanks in advance David.

When I open Thunderbird to my ninja@globalnet.co.uk account it will not sign in and is asking for a new password. When I enter the old password it fails to recognise it when I enter a new password it will not let me log in. Therefore I can not access anything in Thunderbird on my ninja@globalnet.co.uk account. Please send any reply to 52bland@gmail.com.

I deleted one of my emails accounts because it was hacked; I logged in to Ionos (hosting my email) and had to change my password; I changed the password but now I can't reinstall it; Authentication failed; FYI when I use the webmail using the new password, I can check my emails. Please help; Thank you.

Title: Thunderbird 158 – Outlook.pt (IMAP, OAuth2): Microsoft login page never loads, authentication error

Hello,

I can't connect a personal Outlook.pt account (outlook.com) to Thunderbird. The Microsoft sign-in page never appears and I get "Authentication failed".

Environment - Thunderbird 158.0 (64-bit), also tested on Beta; Windows 11 - Browsers installed: Brave and Chrome (Chrome set as default for testing) - Account: personal @outlook.pt, no Microsoft 365 subscription

Settings used - IMAP: outlook.office365.com, port 993, SSL/TLS, OAuth2 - SMTP: smtp.office365.com, port 587, STARTTLS, OAuth2 - Username: full email address

What I have tried - Account setup test says "secure connection to outlook.office365.com:993 established successfully". - Automatic setup: no login window opens; the Error Console shows GuessConfig trying SMTP on port 465 (NS_ERROR_ABORT) and then "authentication failed". - Manual setup with OAuth2 forced: a browser window opens, but it stays on the browser's start page. Once, instead of Microsoft, it showed a Google consent page ("Mozilla Thunderbird Email wants to access your Google Account") for a Gmail address I use elsewhere, even though I was adding the Outlook account. - Clicking links inside emails correctly opens the browser, so the default-browser association works. - Cleared saved passwords/OAuth entries for outlook/office365/microsoft; removed and re-created the account several times. - Created a brand-new clean profile: same result. Thunderbird Beta: same result. - Microsoft account "recent activity" shows no sign-in attempt, so the request seems not to reach Microsoft. - Main profile has extensions (LanguageTool, flagged as incompatible, and CardBook). Not yet tested in Troubleshoot Mode. - Error Console shows no OAuth-related errors besides the GuessConfig lines above.

Questions - Why would Thunderbird open a Google consent page when adding an Outlook account? - Is there a known issue with OAuth2 for Outlook.com in version 158, or a hidden setting that could cause this?

Troubleshooting information from about:support is pasted below. Thank you.

Trying to set up new Gmail account in Thunderbird. New account dialog opens, recognises Gmail address and imap details, but doesn't allow me to provide Gmail with password. Authentification failure results.