Thunderbird Community Forum

I'm struggling to understand where Thunderbird stores everything on a Windows computer so that I can use my incremental automated backup system to keep things backed up.

This support article :

[- Where Thunderbird stores your messages and other user data]

only mentions about the <user>\AppData\Roaming\Thunderbird\Profiles folder but there is also a <user>\AppData\Local\Thunderbird\Profiles folder that appears to be used and needed.

There is a ton of other conflicting 3rd party information out there so I'm hoping for a definitive answer here.

My question is : Can I backup just the '<user>\AppData\Roaming\Thunderbird\Profiles and <user>\AppData\Local\Thunderbird\Profiles and be assured that I will be fully able to recover my email client in the case of needing a complete reinstall ?

Hi,

Since the last update, downloaded on 4 July 2025 to my computer, thunderbird will not download any new emails from my server.

Please assist.

Thanks,

Melissa

Hi, I have been using Thunderbird for many years. I have not made any changes to the standard Windows 10 version.

Suddenly, when I want to open a New Message, the button is highlighted in blue but nothing happens when I click on it.

I have been trying to move emails from a computer to a new one. Nothing works. It tells me to create a zip file since the profile is over 2GB. If it does create one (it usually fails) then when I try to open it with an unzip program it does not appear. I did some snooping and the unzip program says it's empty. Explorer says it's over 4GB. The Windows app says it's an invalid zip file. Obviously TB can't create a valid zip file.

I've tried using just the mail folder because everything else (address book, etc) is not that important. It fails.

I do have the same version of Thunderbird, but the existing computer has the 32 bit version. The new one has 64 bit. Is that the problem?

A couple of months ago TB downloaded an update. The wrong update. I spent hours on it and in a chat for another hour or so. They had me going to different sites and downloading a number of versions. None worked. They gave up. I was told that what I was seeing should never happen. Well it did and they couldn't fix it. I finally dug around in my server and found a few old downloaded versions. One of them finally fixed it.

So, yeah, I've pretty much had it with Thunderbird. If I can't get this resolved quickly (He says after - 6 hours) there is no reason to keep fighting with it.

I found a thread on the TB community forums that said to great a new profile so I did. Now the old PC is screwed. I started another profile import. It's been running for 15 minutes. It is stuck on file 231 and has been for 5 minutes.

If anyone can figure out what to do I'm listening.

I exported a address book from Mailbird as vCard to my desktop. When I import it to Thunderbird it appears with most of the entries blank. The profiles that do appear all have missing data, such as phone numbers and email addresses. This happens with 3 different address books from Mailbird. Malibird only allows export to vCard. It also happens with a older CSV, Excel file I have tried. I am using Thunderbird 139.0.2 (64-bit).

I am running Thunderbird (release 140) with the Dark Theme selected. A few messages are received that are unreadable because of the text color chosen by the sender. I am wondering if there is a method to adjust a parameter for an unreadable message to make it readable. I would prefer not to have to change the Theme to Light for just a few messages!

An example is attached.

I am able to receive emails on Thunderbird but I am not able to send emails to anybody from Thunderbird. That happens on two computers I have. I am able to send emails from Outlook. Therefore, it is not my email provider's (BluePeak) problem. When I try to send an email from Thunderbird, I receive the following error message: “Sending the message failed. SSL received a record with an incorrect Message Authorization Code. The configuration related to must be corrected.”

Please help me resolve this issue. Thank you very much!

After converting from Outlook to Thunderbird, I can see there are 23 unread mails in my Inbox. My problem should have a very simple solution, but I cannot find any. How do I filter my messages in the Inbox to show only those unread???

Bjorn B. Juvkam

In the Settings > Local > Disc Space I have selected: Delete messages more than 61 days old.

In the Local > Trash > [right click] > Properties > Retention Policy, I have also specified: Delete messages more than 61 days old.

Why are the messages deleted from the Trash when I close TB?

I am using version 140.0.1 and wish to rearrange the order of my email accounts if this is possible and easy to do.

I cannot find any guidance on this subject for the latest version.

I received an answer from Wayne to my question about 'How to sort local folders' in Version 140 saying that it is done in Account Settings but I am not seeing that option. Would appreciate more details as to where I can find this option in Account Settings.

I went to use Thunderbird mail on my laptop for the first time in ages. I can receive emails but they won't send:

Log in to server SMTP-mail.outlook.com with username x failed Retry - Enter New Password - Cancel

- I entered the current password, which works fine for Thunderbird Mail on my desktop PC, and checked the box use password manager.

Send Message Error: Sending of the message failed. Unable to authenticate to Outgoing server (SMTP) smtp-mail.outlook.com Please check the password and verify the 'Authentication method' in Account Settings | Outgoing server (SMTP)

Server Type: IMAP Mail Server Server Name: imap-mail.outlook.com I CHANGED THIS to outlook.office365.com - to match the server settings on Thunderbird Mail for my desktop PC - and restarted Thunderbird, but the Log in to server failed message displayed again. Port: 993 Default: 993 Connection security: SSL/TLS Authentication method: OAuth2

I trust I have provided sufficient information for you help me. Thank you!

Before I updated to version 140.0.1esr, I was able to change the background color of my email. I tried Settings>Composition>HTML Style and unchecked use reader's default colors, but that did not work.

Hi everybody,

Thunderbird is not download mail to the client inbox. I created the mailsadress today, freshly installed TB too. I set up the outlook.com account in TB and TB is establishing a connection with the mailserver, but not loading the mails. every time it tries to connect I can see TBgoing through the motions in status in the bottom left. There are mails in the accounts inbox,TB is just not downloading them. I also tried sending mails a mail to myself, from within TB, works fine. The mail sent via TB arrived in the acount inbox, visible in the webapp.

Please help, THX

already double checked Server Settings:

   IMAP:
       Incoming Server: outlook.office365.com
       Port: 993
       Security: SSL/TLS
       Authentication: OAuth2
   SMTP:
       Outgoing Server: smtp.office365.com
       Port: 587
       Security: STARTTLS
       Authentication: OAuth2

I was able to load 1 email perfectly but the 2nd email from the same cPanel will not work. Auto detect and manual settings result in authorization error. The email password is my cPanel login so would be the same for both. Any ideas?

Starting yesterday 4-3-2025 my Thunderbird email keeps locking up and saying it is not responding. I can close it and open it and then work with it for 2 or 3 minutes and it will start not responding again. This is a consistent problem the last few days. I did check and it said there was an automatic update on 4-2-25. I am not sure if this had anything to do with it but i did go in and request an update about 2 hours ago today. This has not helped as I still consistentaly get the not responding problem. Please advise what I can do to fix this.]