Thunderbird Community Forum

We're planning to switch from Outlook to Thunderbird, but we have a hard time in harmonizing font sizes on text and signature. One of the issues is that fonts can be set to textual values tiny, small, medium, etc. w/o knowing what it corresponds to in pt. But lets explain what we tried so far: - Under Settings/ General / Language&Fonts, we defined Calibri 12 as default, what we repeated under Advanced for 'Latin' & 'Other Writing Fonts' - Under Settings / Composition, we defined Calibri / Medium for the HTML Style - The HTML-signature is defined using the Calibri 12 font But when creating a new message w/ these settings, the result is terrible as you can see in the example: disregard the fonts' color, just look at the font sizes.

Is there any simple solution?

I had Thunderbird on my Windows 10 computer. I bought a new Windows 11 computer and downloaded Thunderbird. When I try to set up my email account, I provide my full name (not my Thunderbird user name) and email address. The next screen has the message "Configuration found in Mozilla ISPDB ". I clicked on IMAP and hit continue. The next screen I type in my password for my Spectrum mail account. I have confirmed that the password works went I log onto the Spectrum website. The next screen has the Authentication error "Unable to log in at server. Probably wrong configuration, username or password.". I've also tried using my Thunderbird user name and Password instead of my full name and Spectrum password with the same results. I know my Thunderbird user name is correct but I can't be 100% sure that my Thunderbird password is correct.

I'm not sure if this matters but my email has the has the extension ----@socal.rr.com. This was assigned to me by my original email provider, which was Time Warner Cable. Spectrum bought Time Warner Cable a few years ago and I think Spectrum uses a different extension.

It was working fine on the new computer until yesterday. Now I get a pop-up box that says: ' Unable to connect The connection was refused when attempting to contact localhost.

The site could be temporarily unavailable or too busy. Try again in a few moments.

If you are unable to load any pages, check your computer's network connection. If your computer or network is protected by a firewall or proxy, make sure Thunderbird is permitted to access the web.

Despite my marking messages several times as NOT spam, Thunderbird keeps on and on RE-marking them as spam. And the mails are coming from one of my own addresses, and they ARE in my address book!!!!!

There seems no way that I can stop the beast from misbehaving.

Hello, I can't receive any of my e-mails. I can send e-mails out now. Plus I can put in my password to log into my e-mail. This has been a headache for me, I have been with Thunder Bird for years.

I also get a boxes that says : Unable to write the email to the mailbox. It says to make sure the file system allows me to write privileges, and I have enough disk space to copy the mailbox. I have enough space on my computer system and all. Another box that says my e-mail is being processed. Please wait until processing is complete to get messages. I did e-mail you yesterday on these issues. As I said I can e-mail messages out now also log into my e-mail with my password. Thanks, Chris

Subject: Persistent Column and Folder Layout Issues — Not Being Saved Between Sessions

This is a follow-up to my previous support requests regarding two ongoing problems that significantly impact daily usability.

Column Settings I manage multiple accounts, and my preferred column layout is: Starred, Read Status, Attachment, Subject, From, and Date/Time. I do not use Threads, Correspondents, or Spam Status columns. Despite setting these preferences repeatedly, Thunderbird fails to retain them. Every day I must spend time reconfiguring columns across some or all of my accounts — the state varies unpredictably from one session to the next. This is a persistent, daily frustration that costs meaningful time. Most other major email clients save and reliably maintain column preferences. I'd expect Thunderbird to do the same.

Folder Panel Layout Two problems occur regularly when Thunderbird loads:

Folder order — Standard system folders (Inbox, Sent, Drafts, All Mail, Trash, Spam) should appear at the top of each account. Instead, Sent, All Mail, Trash, and/or Spam are frequently scattered among custom folders, with no apparent consistency.

Folder expansion — Most or all folders load in an expanded state, exposing every nested sub-folder regardless of whether they contain unread mail. This creates unnecessary visual clutter and requires manual collapsing each session.

Again, this behavior is uncommon in other widely-used email clients. Summary These are not one-time glitches — they recur daily and represent a significant usability gap. I'd appreciate confirmation that these are known issues being tracked, or guidance on a reliable fix. Reformatting the interface every morning is not a reasonable expectation for users.

Neither my wife nor I can access email on our respective PCs. This has been the case for four weeks. We can access email by our Android phones, but we really want to use our PCs. I've tried to resolve the problem and failed. Previous to this failure, I had an account with BT but this was transferred to EE. When I attempt to log in to my mail account, I receive the message "Could not connect ... :the connection was refused". I can also add is that in my Account settings, Outgoing Mail server I see a message "Connection to server mail.btinternet.com:465 failed."

Recently it's a daily occurrence that I must enter the password for my SMTP server. I always check "Use Password Manager to remember this password" but it doesn't help. The next day I'll have to go through this again.

I power on my machine multiple times each day, and I use Thunderbird each time. It doesn't happen each time. It seems to happen only the first time I use Thunderbird each day. This is new behavior. Before it would happen now and then, now it's daily.

I don't have a Primary Password. No need for it.

If you need to see the message I can send it to you, but I'm not attaching it right now because it shows my email address and the smtp destination. Maybe I'm being too careful.

Lorsque j'essaie d'ajouter un nouveau compte, la configuration est trouvé dans la base de données des FAI de Mozilla, je clic sur "continuer", dans la fenêtre Popup j'autorise Thunderbird a accéder à mes informations, ensuite j'ai le message "erreur d'authentification". Pourtant mon mot de passe est correcte.

I had to reinstall everything after a Windows glitch. I always liked to have Thunderbird show a list of my emails with a window below to show the content of emails I selected in the list. But now I can't find anything in settings to allow me to do that.

A substantial portion of email spam that I receive has a couple of characteristics: - the subject line includes "Sonic", and - the sender is plainly not Sonic.

For example:

Return-Path: <live1@tomokawasaki.or.jp> Received: from tomokawasaki.or.jp (tomokawasaki.or.jp [122.1.223.161]) by mwb-sdgw-mts-005c1.ocn.ad.jp (Postfix) with ESMTP id 063B61400008F for <ronks@sonic.net>; Sun, 19 Jul 2026 07:07:06 +0900 (JST) From: =?UTF-8?B?U29uaWMg0JLRlmxs0ZbQv2c=?= <live1@tomokawasaki.or.jp> (From translates to "Sonic Billing" here; in other spam it is cleartext) Subject: Automatic Payment Unsuccessful To: <ronks@sonic.net>

I am wondering if it is possible to construct a filter that says basically: If Subject includes Sonic AND From does not include Sonic Then Send to Trash (or mark as spam or whatever)

Can this be done?

Hi

I have set up Thunderbird with a Zimbra mail serveur (Zimbra serveur 10.1.10_GA_4785) using the EWS new feature of Thunderbird.

I can setup the EWS account. The test of the secured connection to the server is returned valid. But in the mailbox, the list of folder is empty, and I see no email. Interestingly, I can successfully send email from this thunderbird using the exchange server as sending server.

To resume, no emails are received, but sending emails works.

So, I check the request to the exchange server when starting a synchronization : Here the result : Request : <soap:Envelope xmlns:soap="http://schemas.xmlsoap.org/soap/envelope/" xmlns:t="http://schemas.microsoft.com/exchange/services/2006/types"><soap:Header><t:RequestServerVersion Version="Exchange2010_SP2"/></soap:Header><soap:Body><GetFolder xmlns="http://schemas.microsoft.com/exchange/services/2006/messages"><FolderShape><t:BaseShape>IdOnly</t:BaseShape></FolderShape><FolderIds><t:DistinguishedFolderId Id="msgfolderroot"/><t:DistinguishedFolderId Id="inbox"/><t:DistinguishedFolderId Id="deleteditems"/><t:DistinguishedFolderId Id="drafts"/><t:DistinguishedFolderId Id="outbox"/><t:DistinguishedFolderId Id="sentitems"/><t:DistinguishedFolderId Id="junkemail"/><t:DistinguishedFolderId Id="archive"/></FolderIds></GetFolder></soap:Body></soap:Envelope>

Response <soap:Envelope xmlns:soap="http://schemas.xmlsoap.org/soap/envelope/"><soap:Header><ns2:ServerVersionInfo xmlns:ns2="http://schemas.microsoft.com/exchange/services/2006/types" xmlns="http://schemas.microsoft.com/exchange/services/2006/messages" MajorVersion="14" MinorVersion="3" MajorBuildNumber="158" MinorBuildNumber="11" Version="Exchange2010_SP2"/></soap:Header><soap:Body><GetFolderResponse xmlns:ns2="http://schemas.microsoft.com/exchange/services/2006/types" xmlns="http://schemas.microsoft.com/exchange/services/2006/messages"><ResponseMessages><GetFolderResponseMessage ResponseClass="Error"><MessageText>Cannot invoke "com.microsoft.schemas.exchange.services._2006.types.DistinguishedFolderIdNameType.value()" because the return value of "com.microsoft.schemas.exchange.services._2006.types.DistinguishedFolderIdType.getId()" is null</MessageText></GetFolderResponseMessage></ResponseMessages></GetFolderResponse></soap:Body></soap:Envelope>

The parameters ( domain replaced by *** for privacy) mail.ews.server_versions : {"https://zimbra.*******.com/ews/Exchange.asmx":"Exchange2010_SP2"} mail.outgoingserver.ews1.auth_method : 3 mail.outgoingserver.ews1.ews_url : https://zimbra.*******.com/ews/Exchange.asmx mail.outgoingserver.ews1.key : ews1 mail.root.ews-rel : [ProfD]Mail mail.server.server4.ews_url : https://zimbra.******.com/ews/Exchange.asmx mail.smtpserver.ews1.type : ews

Anyone successfully used the new EWS feature with Zimbra server ?

PS : I confirm the EWS connection with the Zimbra serveur by successfully using EWS on Outlook for android.

I use Thunderbird when Postbox acquired another. I am using 2 computers - desktop, old (10+ years), still Windows 10, and 2 two emails; new laptop (traveling), Windows 11. I download Thunderbird and set up my accounts - gmail.com and twc.com. Troubles with gmail.com, but finally I set up. However, I can't set up twc.com. I like twc.com-- no reason. (Time Warner Cable (twc) bought Spectrum. ) I can login twc.com webmail. Not Thunderbird. I looked carefully set up, Thunderbird searched, found "Host: mobile.charter.net" (Huh?, , continue, enter my password - "Error: ---". I removed VPN Windows 11, no difference. (Curios, my laptop and Firefox, my bank rejected connection. My desktop and Firefox still connects! I dread the day must update.)

I am look forward yours reply. (Maybe Spectrum is searching to dump twc.com.) Jeremy Fields P.S. I wrote with my desktop - windows 10 -, my new laptop (windows 11) is problems

Today when I started Thunderbird two of my email accounts are Highlighted in RED with a RED Triangle at the end of the email address.

Both accounts are from Spectrum. My other email accounts from another provider are OKAY.

I am not able to retrieve or send emails on these two accounts. I can get my emails from both accounts when I use Spectrum Webmail. So it looks like the account information is correct.

How do I fix this?

Hi all,

I installed Thunderbird a few months ago to transfer emails from an email account that is about to be shut down to my Google email account.

I now want to uninstall Thunderbird (and delete all its files from my computer, including emails) but am worried my Google emails will also get deleted (e.g., due to syncing?) in this process.

I would have loved to keep Thunderbird installed but, due to my personal laptop being unavailable when this email transfer began a few months ago, I had to install Thunderbird on my work laptop instead, and I do not want Thunderbird to stay on my work laptop anymore (my employer allows employees to install any software but I will feel better if I just delete Thunderbird from the work laptop at this point).

Please advise, thanks.

Migrating from a Win 10 laptop to a Win 11 laptop. Need to move the local folders as well but they were assigned a different ID and I can't change the target address in the new installation. Thanks in advance for your help. Rick.

Hello,

When I forward message with some attachments, new windows opens, with e-mail and attachments, and I can open and review them. If I edit (or not) that message, for no more than couple minutes, I can send it without problems.

But if I left windows open for some time (let say more than 10 minutest, but I not figured out exact amount), I can't view attachments. If I double-click on icons, nothing happens. If I try to send that message, I get message about missing file.

I've noticed, that after opening new window with forwarded message, attachments are copied to %TEMP% folder as nsmail.pdf (or jpg or something). After some time (10 or more minutes as mentioned before) these files disappear, and then problem begins.

The same problem occurs with MAPI generated message with attachment.

Problem tested at two PCs, one PC with 32bit viersion of TB and IMAP, and another with 64bit and POP.

I would like to follow up on a query I posted earlier this year at https://support.mozilla.org/en-US/questions/1565806

Briefly, I want to move some more prior years' archived folders and messages to TBird's Local Folders. My effort to simply drag and drop the archive to the new location ran into trouble because (as I understand) the archive flag was not turned off in the move, leading to anomalous results. Is there a standard approved way to move archived messages to local folders, or should I just drag and drop and de-flag again?

From my earlier query: > Installing the folder flags add-on showed me (as you said) that 2024 was flagged as an archive. I turned the flag off, restarted TBird and 2024 now comes after 2023 as it should. I expect I created the problem somehow when I moved the 2024 folder from the server to Local Folders; what is the proper way to do that?