Thunderbird Community Forum

In reference to the article [[Knowledge Base Article|http://mzl.la/1ApHiU3]], "Move Thunderbird data to a new computer", this misses the transfer of Local Folders.

The instructions only include moving the Thunderbird application data folder with profile information but does not include Local Folders, after completing these instructions the Local Folders will not be present on the new computer.

The path for Local Folders is under Account Settings > Local Folders, this folder needs to be copied to the similar path on the new computer as well.

I have copied emails from a Windows 10 to Windows 11 computer using these instructions and it appears to work.

Cannot send or receive email all of sudden in Thunderbird. When I the click the messages icon, nothing happens, and I get "Could not connect to server mail.twc.com; the connection was refused". When trying to send a m,message I get "Sending of the message failed. The message could not be sent because connecting to Outgoing server (SMTP) mail.twc.com failed. The server may be unavailable or is refusing SMTP connections. Please verify that your Outgoing server (SMTP) settings are correct and try again." No settings were changed and everything was fine when I put the computer to sleep. This happens on both a Win 7 and 11 machine Email is a Time Warner (now Spectrum) Road Runner account (twc.com). Spent an hour with Spectrum, and they say this is a third party (Thunderbird) issue. A friend has the same setup, and is having the same problems that started at the same time. Win 11 version 150.02 Win 7 115.18.0 (latest available for win 7)

Appreciate any help....

I have followed the instructions to txfer the profile to new PC W.11 - from W.10. T'bird says: "Your Thunderbird profile cannot be loaded. It may be missing or inaccessible."

I have the old folder from 'roaming' pasted in correctly - did it twice. No change.

I also have all my message folder ready on the new PC. These are held in a better location for bak up. When I moved to the last machine - nine years ago - I had exactly the same problem!

As new install will not load the profile I cannot get into it to tell it anything.

Suggestions welcome. SCA

Outlook for Mac will no longer support local folders sometime in October 2026. I need to move my local folders to Thunderbird. I don't see any options for doing this.

Thunderbird locked up. Followed forum advice to reload Thunderbird. Identified legacy abook.sqlite and history.sqlite files but these will not import to reloaded Thunderbird. Confirmed these files are not read only. Any advice much appreciated..

"Thunderbird is being managed by your organization." how to get rid of this? my mail is effectively blocked :( says: DisableAppUpdate: active

Policy Name 3rdparty Set policies that WebExtensions can access via chrome.storage.managed.

I won't be able to see your reply... please use b[redacted email from community support forum]

При регистрации аккаунта в почтовом клиенте выдает постоянную ошибку, ссылая на то, что исходящий сервер уже ссуществует. Почта .com При этом ранее аккаунт был создан и все прекрасно работало.

Hello, I urgently need help recovering emails and archive folders that have disappeared from Thunderbird.

Here is what happened: I had an email account configured in Thunderbird using POP3. Over the years, all the emails and the entire email history were downloaded and stored locally in Thunderbird. I also had several archive folders containing important emails and documents.

The mailbox was recently moved from the old mail server to a new mail server using IMAP. The account was then set up again in Thunderbird as a new IMAP account.

The old POP3 account/configuration was left untouched, because I expected the old emails and folders stored locally in Thunderbird to remain available.

However, after setting up the new IMAP account, I can no longer see the previous email history or the archive folders from the old POP3 account. Some of these folders contain very important documents that I need to recover.

I would like to emphasize that I am not asking to recover emails from the old mail server. The emails and archives had previously been downloaded and stored locally in Thunderbird through the POP3 configuration.

Could you please help me determine, how I can locate and restore the old Thunderbird profile or Local Folders? The emails and archive folders are very important, so I would really appreciate detailed instructions on how to safely recover them. I have not intentionally deleted the old emails or archive folders.

Technical information: Email address: biuro@wojciechprzybylski.pl Old mail server: server.go4win.pl Old account type: POP3 Approximate date of the migration: 15.09,2026 Missing folders/emails: Archiwum

Thank you very much for your help.

Best regards, Halina Kaczyńska

Hi,

I remember i tried 7y. ago a email certificate signed with SHA3, it was not OK.

I tried again now, and it is still blocked.

1) the certs can be added in the account settings > S/MIME for signature and ciphering, with a warning. 2) then creating a new email, the recipients certificates are not detected (while configured in another account on the same thunderbird client), and forcing ciphering is not allowed with the error message

"Sending of the message failed. This message cannot be digitally signed because the signing certificate selected in your End-to-End Encryption settings is not valid for this operation. (The certificate was signed using a signature algorithm that is disabled because it is not secure.)"

"Unable to save your message as a draft. This message cannot be digitally signed because the signing certificate selected in your End-to-End Encryption settings is not valid for this operation. (The certificate was signed using a signature algorithm that is disabled because it is not secure.)"

Even, when using only ciphering, and no signature in S/MIME.

The parameter mail.smime.accept_insecure_sha1_message_signatures do not change the bahavior.

-> Can Thunderbird allow SHA3 usage, please ?

Even if thunderbird does not want to generalize it, mozilla may create a parameter by default false

mail.smime.accept_sha3_message_signatures

Best Regards, Gwenolé

I'm assiting an elderly user of Thunderbird. We were trying to update his saved password but the menu items did not match my current version 153.3.1esr. When I asked him to check his version he had options to update from v52. He went through 3 update cycles to v78 when all his data had disappeared. I found some information at: https://support.mozilla.org/mk/questions/1312391 which seemed to put the issue at a file format change in v78. When he looked at the profile folders the most recent was created in 2024. (I couldn't get him to find a modified date more recently.) When he closed Thunderbird and used the Run command "Thunderbird.exe -P" we couldn't find a way to select that most recent profile folder. Are you able to give me instructions I can use in a Windows remote (quick) assist session to restore his data from the profile folder?

Alternatively, is it possible to downgrade back to v68 of Thunderbird; would this restore his data (account settings, emails, contacts/address book etc?

Thanks in advance for any guidance you may be able to offer.

For a few days I'm having trouble with Asana mails (notification mails informing me about replies, comments, etc).

Clicking on the mail to view it freezes Thunderbird for a good 5 seconds while one CPU core spins at 100%. This only happens with Asana mails (or at least I haven't found any other problematic senders).

I guess it's a problem with validation or parsing of the mail's HTML content. But I don't know how to debug this.

I can't pinpoint exactly when it started happening, but it was around the time I've switched to the [new snap release track](https://support.mozilla.org/en-US/kb/channel-choices-thunderbird-snap-and-flatpak#w_snap-channel-changes-in-2026). But since this happens with Snap and Flatpak I think the culprit may be the 153.0 update.

Things I've tried:

• Clearing cache and msf files.
• Troubleshooting mode with add-ons disabled.
• Reinstallation. Creating new profile + importing old data.
• Switching from Snap to Flatpak
• Switching Message Body display to Plan Text or Simple HTML.
• Disabling HW acceleration.
• Checking console for suspicious output.

Anything I can do to create handle the problem or collect information for a proper bug report?

I really hope somebody can help me with the "Google-4-TbSync is incompatible with Thunderbird 153.3.1" Are there any solution to this, because the developer seems to have stopped the development of an update of this extention. I desperately need to sync my Google contacts with my Thunderbir contacts. Any help will be welcomed.

In the search results overview, incorrect email addresses are sometimes additionally displayed in the 'Recipient' and 'From' columns. (Taken from the email directly located above it.)

Win 11 Home 25H2 Thunderbird 156.0.1

We are unable to add a corporate Microsoft 365 mailbox to Thunderbird. During OAuth sign-in, Microsoft shows “Need admin approval” and Entra logs: AADSTS90094: Admin consent is required for the permissions requested by this application. We have confirmed: - Thunderbird App ID: 9e5f94bc-e8a4-4e73-b8be-63364c29d753 - User assignment is not required - The tenant allows microsoft-user-default-allow-consent-apps - Thunderbird is included in that policy - No exclusion rule is configured - Conditional Access and sign-in risk are not causing the failure - A clean Thunderbird reinstall/profile still gives the same error Existing Thunderbird users still work, but some newly configured users cannot complete OAuth consent. Has anyone seen this recently, or is there a known Thunderbird/Microsoft 365 OAuth issue affecting new account setup?

My "Bulk Mail" folder is not where it belongs, it is attached to a sub folder of a personal folder. I would like to get it move back to it's original location, or under trash, but all attempts have failed. Than you.

Lately, Thunderbird has been using excessive CPU time even when idle. I am on Windows 11 and running the 153.3.1esr release of Thunderbird. It's impacting other applications. When I exit Thunderbird, everything runs faster. Right now it's using over 7% CPU and about 500 MB of ram.

Hardware is HP Pavilion Desktop 590-p0xxx. Intel i5-8400 2.8 GHz 12 GB ram.

I am using an email server that currently is using certificates that have expired. That problem is being worked on. In the meantime, whenever I access the server to open a folder, I get a pop-up notification telling me that the certificate has expired. I go ahead and confirm the security exception and check the box to permanently store the exception. Trouble is this ISN'T being persisted, when I open a different folder I have to go through this process again in order to access my emails in that folder.

Me thinks you got a bug in your software Kemosabe!