Thunderbird Community Forum

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?

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

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.

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.

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!

Hello, I hope you are doing well.

I spent several hours yesterday and today moving all my Gmail messages to my Yahoo account in Thunderbird on Windows 11 25H2 Home in the United States.

I expected my emails to appear in my account when I logged into the Yahoo Mail site. Instead, my account has no messages at all.

How can I correct this? I don't want to lose all my emails, I want them in Yahoo instead.

NOTE: Please change my email address to JAL1862@yahoo. I am closing my Gmail account by the end of the day on September 30.

Using Thunderbird with Windows 11. Yesterday I could send/receive Emails OK. Today I cannot use either. Didn't change anything. When I try to send message, a box with this message appears: "Login to server smtp.gmail.com with username [redacted] @gmail.com failed". I am logged in to my Google account. A few months ago, the same thing happened. Gave up for the night and the next morning everything worked OK. Is Thunderbird occasionally out of service? I tried Microsoft Outlook and it works OK so I know internet is OK

Also, I notice receiving messages takes a long time sometimes. I get messages sometimes a full day later. Outlook is almost instantaneous. If I send a message to me, it is received within seconds. Any suggestions? Regards, Art Towslee [redacted] @gmail.com [redacted] (cell)

/edited email and phone# from public community support forum

I have a completely vanilla install of TB fully up to date as of this writing [it is version = 156.0.1 (aarch64) and I checked for updates], no extensions, no proxy, on a new OSX 27.0 (Golden Gate) computer and even when idling it is using substantial resources. The only thing even remotely non-basic is their is the Proton Mail Bridge to connect to Proton Mail for one of the linked email accounts, but that is its own little program with its own threads and takes almost no system resources even when sending or receiving mail (which is not happening currently.) Look at the attached screen shot.

In the screen shot I have left Thunderbird to idle for about an hour. No new mail in that time and other then clicking on or off the window to bring it to the fore I have not interacted with the program at all myself. Meanwhile Thunderbird and its Thunderbird GPU Helper are using substantial amounts of the CPU and GPU, have a combine total of 86 threads (more then any two other things running except the kernal tasks) and are hogging ram (not depicted).

Meanwhile among a few other applications (Apple Music, OfficeLibre, etc...) I also have Brave Browser opened in the background running with two windows and a total of 8 tabs wherein Brave is actively downloading GB of data from MEGA as well as performing other admittedly lighter tasks. Even when doing all this, Brave barely registers on computer resources compared to Thunderbird and Thunderbird GPU Helper when they are just idling.

Is this all proton mail's fault with the Proton Mail Bridge? If not is there anything I can do to quell the hunger for computer resources of this voracious beast of an email client that is TB and uses resources as if it were a video game even when idling?

This would be a new account as my existing Mailbird stopped working. I am on Windows 11 laptop and it appears that the last windows update excluded Mailbird from allowed. While setting up cannot get past the error msg that says Host name and port error. there is no window to enter a port number. Host name I am not sure but tried a few and talked with Rogers and they could not help, They said ask Thunderbird. I am at a loss. tried: imap.shaw.ca; mail.shaw.ca; shawmail.vc.shawcable.net and more that I found in notes.

As we sunset the WP Forms that we’ve been using for Distribution List Changes, I need for everyone to update the link in your signature for Distribution List Changes. My signature doesn’t have that line because I email so many people beyond clients…

Your signatures of course do have a line that invites clients to click here in order to submit change requests for their distribution lists.

Moving forward – please use this link as the hyperlink within your signature.

Please confirm with me once done, and let me know if you have any questions.

https://forms.zohopublic.com/thereputationlab1/form/HotelDistributionListChangeRequest/formperma/YaaOZ8YW6VUts9pHXv40s16zGZZKO3V9N3SuHPBbV9w

This is from my boss. How do I do it?

I have an account - david.woodcock@skynet .be that is no longer active. But Thunderbird is still trying to connect to it and download messages. How do I stop Thunderbird from trying to access this account?

Thunderbird won't download messages from the email account that we have at . It was working perfectly last week, but starting Friday it will start to download the messages, but never does. Eventually, it displays the following error: Unable to write the email to the mailbox. Make sure the file system allows you write privileges, and you have enough disk space to copy the mailbox. What can I do to fix this? Or, can I downgrade to an earlier version that will work? Thanks, Graham [redacted email]