Thunderbird Community Forum

In the last month or 2, when I delete an email it does not show in the trash folder. I can wait from 5 minutes to even the next time I reboot my puter to finally see it it trash. Sometimes it sends it to the all mail or important folder instead of trash. And if I delete from there, it still takes tons of time to end up in the trash folder...if it even gets there. This seems to be getting worse by the day. I have clicked repair folder, no change, I have cleared Thunderbird's cache, no change. It's also now taking way too much time to load an email that contains a picture. This happens with at least 3 of these gmails. I'm at a loss here and extremely frustrated and about to change these gmails from imap to pop. win10 and TB is up to date. But it doesn't compact folders as much as it used to either. Any help appreciated

I have used Thunderbird for years, for two different work accounts and a personal account. I am retiring from one workplace, a small arts charity which runs occasional arts events for which I work from home using my own set up. My successor uses Outlook so I want to save relevant emails for them to be able to access previous correspondence if they need to. If I save relevant emails as .eml files into a folder in Dropbox, should my successor be able to open them in Outlook? If not, is there another solution apart from printing relevant emails to PDF and saving them? I am not a hugely techie user and generally find Thunderbird very straightforward! Many thanks for any advice! CathGuth

A few times I have missed messages that have have been inadvertently placed in the Accounts Spam Folder. Is it possible to to indicate that the Spam Folder has contents in the same way contents are indicated in other Account Folders?

I've been a longtime Thunderbird user on my desktop (laptop actually). I'm wanting to start using Thunderbird on my Android phone.

What I understand so far is that both the desktop and mobile have to have the same settings if I want to be able to send/receive (and have records) on both setups. I also understand that I need use IMAP settings.

In my situation, I believe I set up my desktop to be POP but to leave messages on server until I deleted.

So, my questions are these: Do I need to delete my POP accounts on my desktop first before adding the IMAP version of the account? If not, I can simply add the new account along side and then delete the old account. If I do need to delete the account, does deleting the account delete the emails as well? And how do I transfer any emails or sent emails from the POP to the IMAP?

In as much as I have several accounts to transfer, I want to make sure my step-by-step works well for one then I can proceed to all the rest.

Thx BobbyG:)

I am trying to migrate from Microsoft Outlook 2021 to Mozilla Thunderbird. I have successfully imported the email from a number of different email accounts. I would now like to import the archived emails held in a number of PST files. The import tool would seem to be what is required, but it does not seem to allow me to select the PST files that I wish to import. I am concerned that it will try to import all email messages from my Outlook 2021. Is there a way of restricting it to just individual PST files?

I am using thunderbird client on arch linux. I am trying to filter by adding "Reply-To" as a filter. If i look into the source of the email i am trying to filter (i get like 100s of spam messages and only the Reply To seems to be from the same domain in the end) the Reply-To appears in there.

Any idea how to fix that? The other rules work fine, this one only seems to not work

I have used Thunderbird with the same email account for years, creating subfolders and moving emails to the subfolders with no issues.

With Thunderbird 153.0.1, after creating a new subfolder in the account, when attempting to move emails to the new folder, I receive the following error:

"Thunderbird: The current command did not succeed. The email server responded: APPEND invalid flag list"

Hello,

My internet provider is RCN. For the past couple of months, I’ve occasionally been getting the message, “Connection to server imap.rcn.com timed out.” As a result, I’m unable to receive emails via Thunderbird.

All my settings are correct. Usually, the problem resolves itself within 24 hours, but sometimes, like this time, it lasts longer.

Any suggestions? Best, Magda

I have had Thunderbird from the time I acquired my Mac computer. This week it started to do something new. After a restart I opened Thunderbird. A box came up that says across the top System Integration. The cursor balloons, and hasn't stopped for the time I powered the computer, as least fifteen minutes. You know how the program icons are in a dock across the bottom. With other browsers open, hitting the Thunderbird icon doesn't bring its window into the forefront. This needs either a reset, or possibly a backup first. Is there a quicker way to fix this? Thanks in advance. I am not using a VPN; but I also have Thunderbird on my Windows 11. You might have seen a more recent thread on that installation. I included a screenshot. It was easier here to do that than on the Windows 11. On the Mac, I just had to use Activity Monitor to close out of Thunderbird in order to get its version.

My folders are in disarray and it is cutting into my productivity to file emails. I have tried but it in settings but it doesn't work. Many are in alpha order but there are 2 different two different sections of the same name, and some odd files end up in an alphabetized section.

For instance there are 2 different ZBV sections with other stray folders in the same area that should be in there own alpha folder area. It's a mess to find the right folder. I have to scroll up and own and look for the folder I need to file in. I would be happy to donate, and i have in the past, but I really need this to get fixed. Please, please, please...

I am assisting an elderly user with a personal @hotmail.com account that receives email successfully in Thunderbird but cannot send. I have confirmed they can send and receive emails from their online outlook.com portal. The user's computer setup is as follows:

• Windows 11 (with latest updates).
• Thunderbird 153.0.2 (64-bit).
• A personal @hotmail.com account with the following server configurations:

  -> Incoming IMAP: outlook.office365.com, port 993, SSL/TLS, OAuth2, and
  -> Outgoing SMTP: smtp-mail.outlook.com, port 587, STARTTLS, OAuth2.

Thunderbird successfully authenticates to Microsoft using OAuth2 for incoming email. However, when Thunderbird attempts outgoing email authentication, Microsoft's SMTP server rejects the authentication. The Error Console in Thunderbird records this message: "535 5.7.139 Authentication unsuccessful, SmtpClientAuthentication is disabled for the Mailbox."

-> Refer to attached image: "Thunderbird Error Console_20260811.jpg". -> I am able to provide a short screen recording demonstrating the failure if needed.

To try and resolve the above, I completed the following actions:

1. Confirmed Thunderbird is current (153.0.2).
2. Confirmed SMTP is configured for OAuth2 rather than Normal Password.
3. Confirmed port 587 and STARTTLS.
4. Re-authorised the Microsoft account/OAuth connection.
5. Confirmed IMAP OAuth2 works.
6. Confirmed Outlook.com webmail can send successfully.
7. Reviewed Mozilla's current “Microsoft OAuth Authentication and Thunderbird in 2026” guidance, including the section covering cases where IMAP/POP works but SMTP does not.
8. Captured the SMTP failure in Thunderbird's Error Console.

However nothing worked, so I raised the matter with Microsoft support and eventually had the matter referred to their Tier 2 team. The Microsoft case number is: 7107041963.

Microsoft Support confirmed that for a personal Outlook.com/Hotmail account there is no user-accessible mailbox-level SMTP AUTH setting, and advised that SMTP is enabled by default for supported clients. However, because sending from Outlook.com webmail works, Microsoft Tier 2 declined to investigate the SMTP server response further and directed me to Thunderbird support.

I am able to provide a copy of the chat transcript if needed.

In any event, the TLDR version IMAP works using OAuth2, but SMTP using OAuth2 fails because Microsoft's SMTP server reports SmtpClientAuthentication is disabled for the Mailbox. Microsoft Tier 2 has referred the issue to Thunderbird support.

Questions:

1. Is this a known current issue affecting personal Outlook.com/Hotmail accounts using Thunderbird?
2. Is 535 5.7.139 SmtpClientAuthentication is disabled for the Mailbox known to occur with Thunderbird OAuth2 even though IMAP OAuth2 succeeds?
3. Is there a current Thunderbird-side workaround or alternative SMTP server/configuration recommended for personal Hotmail accounts?
4. Would changing the SMTP server from smtp-mail.outlook.com to smtp.office365.com be appropriate for a personal Hotmail account in Thunderbird 153, or should the current Microsoft-documented server be retained?

-> I note there appears to be conflicting advice on this point in previous support threads.

1. Given that IMAP OAuth2 authentication succeeds for the same Microsoft account, does this indicate that Thunderbird's Microsoft OAuth authorisation itself is functioning correctly, or could SMTP require a separate permission/token that may be failing?
2. Are there any additional Thunderbird logs or diagnostics I can provide that would help resolve this matter?

Disclosure: I used ChatGPT to help organise my troubleshooting notes and technical details for this post. The troubleshooting, observations and diagnostic information described above are from my own work on the affected PC.

Sometimes an email I receive contains text whose right margin and text is chopped off. I thought this was because the emails were formatted for Google's gmail, but I just received an email from Thunderbird itself that is truncated this way. What's going on?

I'm enclosing a screen shot. I can also send the .eml file if that's helpful.

My Thunderbird does look strange, though it works alright. It annoys me, there are black-gray rectanguler spots left top and bottom. It dissapears when in full screen mode. It is not in any other program. I add a picture. Is there anybody who knows how to solve this. Thanks, Hans, Netherlands

TB guidance is to maintain separate profiles for dual-booting (Kubuntu and Win11), rather than sharing the profile. That adds to IMAP churn, but also to disk space, of course. But the biggest concern is keeping Local Folders (a very large archive which is by far the largest part of my profile) coordinated: both sides must access the same Local Folders.

The option to specify "Message Storage" for Local Folders obviously addresses that problem: both Kubuntu and Win11 can have the same NTFS Local Folders storage. At the same time, each IMAP account also has the option to specify its own "Message Storage" "Local Directory" location outside of the profile folder. That suggests two obvious questions:

1. Why not specify shared storage for each account, as well as for Local Folders?
2. After Local Folders and all accounts are shared, then precisely what, from each profile, cannot be shared between Kubuntu and Windows? Does this bring us back to asking why the profile cannot simply be shared?

[Years ago, when my email accounts were POP, I had no problem sharing a profile between WinXP and an earlier Ubuntu variant. (Of course with POP, they had to share.) Is today's separate-profiles guidance related to IMAP accounts or to some other change in TB design?]

Hello. Thanks in advance. I spent a couple of long evenings deleting a few thousand sent emails from Thunderbird in order to free up some memory on my notebook computer and then intended to create a new backup profile. However, when I tried to do so using the Thunderbird Export tool an "unexpected error" occurred and I discovered that there was no longer a Thunderbird profile folder in Windows/Users/[my name]/appdata/Roaming or Local. When I used the Troubleshooting Information tool to look for the folder under Application Basics/Profile Folder, clicking on 'Open Folder' did nothing. The location is seemingly 'unavailable' for no apparent reason. Thunderbird still opens and closes normally, I can send and receive emails and all my emails are still there. I have an older backup profile stored on a removable disc, but it pre-dates the mass deletion of sent emails. My question is: if I install Thunderbird on a different PC and import this older backup profile, I presume all the emails I've just painstakingly deleted off my PC will reappear, but can Thunderbird connect to the server and download my stored emails as they were most recently saved (without the thousands of unwanted sent emails) so I can create an up-to-date profile? Thanks in advance for any advice.