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Hi! I am trying to use the Thunderbird application to help me view a huge '.mbox' file from an email account that is no longer active. I have the entire file saved to my computer as I downloaded it before the account was closed. Can you help me access those files? I am working on a huge project and really need to look for date sand times of emails sent in the mailbox so that i can piece together the timeline of the project. I would greatly appreciate this!!!

Went to search for someone in the Quick Search and it did not bring up their emails in the folder, which exist as I confirmed by sorting alphabetically and finding them. Why is this?

Hello.

1. How to save a tab group without closing it? 2. How to make individual tabs in a tab group permanent? (So when you close a tab group only the permanent members are preserved.)

I have a Fedora laptop which has run Thunderbird on KDE Plasma for years.

I typically put the Thunderbird window on my big monitor where everything works as expected.

When I move the window to the laptop screen (or unplug the laptop and use it without the big screen), I can navigate the folder list in the left-hand pane, but the list of emails and body panes on the right do not display, only the Welcome screen.

When I put Thunderbird in Help > Troublehoot Mode, all works as expected.

The only special add on I use is the Get All Mail button.

Just received message, by LIFEHACKER, originally discovered by LAYER X, about "17 malicious extensions across numerous browsers", the list which includes Firefox and is supposedly a recent event outside of the earlier (?) event involving the Malware Ghost Poster in downloads previously cleansed by Firefox. Is this old news or is there more Malware that is 'out there' or that could be on my computer without my knowledge? (I do not download willy-nilly....) Would appreciate valid insight if it is just repetitious/old info rehashed for shock value. Thanks!

Have no idea to whom I was chatting a week or so ago, but outlook.office365.com was recommended to me as the incoming server setting for Outlook.com. Set TB that way and used it for a week or so. TODAY got a "failure to authenticate" error from TB (have had many such errors before). Went directly to Copilot, as I thought it would be the most authoritarian place to clear up Microsoft problems. It provided the informaiton below: Official Outlook.com Thunderbird Incoming Server Settings (2026) IMAP (recommended) Settings Server name: imap-mail.outlook.com Port: 993 Security: SSL/TLS Authentication; OAuth2 Username; Your full Outlook.com email address

Why this is the correct server Outlook.com, Hotmail, Live, and MSN accounts do not use outlook.office365.com .

Set outlook account incoming server to imap-mail.outlook.com and reset TB Immediately got: Mozilla Thunderbird Thunderbird Authentication failure while connecting to server imap-mail.outlook.com.

Can someone please tell what's going on?

This morning, I repeatedly received an "Authentication failed when connecting to outlook.office365.com" error. I removed the Outlook account from Thunderbird hoping to solve this by reconnecting and starting from scratch. Upon entering my email and password, my configuration is successfully located in the Mozilla database, but upon selecting the IMAP configuration and after a brief password check, I received the error message "Unable to log in at server. Probably wrong configuration, username or password". Is this an issue on Outlook's end, or is something not set up properly?

Can't access or re-add my existing outlook account to thunderbird 147.0. Tried using my password, an app password. Nothing. Keep seeing the same error over and over again.

My Hotmail account suddenly stopped working today (was working yesterday). Thunderbird shows a popup saying authentication failed, but doesn't ask me to try a different password (not that I changed it recently).

The error details are only visible in Error Console:

Got an error name=oAuth2Error, the server said: Authentication failure: unknown user name or bad password.

Using server: outlook.office365.com, port 995 (POP) user name: ****@hotmail.com SSL/TLS, OAuth2

I need to fix TB to send/receive/save emails after a power failure today, Grid outage at 13:40, Power restored 13:40. Computer restarted, TB opened but will not perform any send/receive/save tasks. TB Message Send gets Outlook notification - Authentication failure. Went to Outlook email, logged back in, test email I had attempted to send by TB is in Outlook, plus new emails in Outlook, but none in TB. Checked for TB updates, current as of Jan 15, 2026. Restarted computer twice. Outlook email works but TB does not perform any tasks. I lost no TB emails in my messages before the power failure, they are all still in my TB messages. I have Firefox Browser and Windows 11. I love TB. It has had cardiac arrest. Help. Ann

AT&T/Direct TV Tech Wizards tell Me that your Web Browser is too SECURE... I pay all my Bills using MOZILLA Web, never have a problem. 2 Months ago I have had problems logging on to Direct TV web site to pay my bill. They tell me its your web site... I even told them that I have no problem logging on to Government Web Sites. Can you help me?