Thunderbird Community Forum

When all the comcast accounts migrated to yahoo, there wasn't supposed to be a change but I cannot send or receive messages through Thunderbird. I deleted my old passwords and tried to use the one that works at yahoo but it is not working.

Apparently I also have 3 thunderbirds running on my machine .  I don't know how to get rid of the old ones

I also got an error message that says 151.0.4 is not compatible with 151.0.3

My recollection is that prior to a recent automatic update to Thunderbird 140.12.1esr (64-bit) when I had a message composition window open, there were "SEND" button and possibly a "SEND LATER" button (to the left of the addressee and cc addresses in addition to the keyboard shortcuts (CTRL ENTER and CTRL SHIFT ENTER).

Following the update, there is no longer anything to the left of the addressee information. I have checked the toolbar menus, and there do not appear to be any button options. I can still send messages, but the lack of the buttons is a hindrance.

Перестали отправляться письма с почтового ящика gmail.com. Соединение с сервером исходящей почты не устанавливается. Разные порты и способы шифрования уже пробовал. помогите решить проблему. Спасибо.

In Thunderbird 151.0.1 [64 bit] I get the following error message: Error Inbox - inbox on .....[my email address] "There is not enough disk space to download new messages. Try deleting old mail, emptying the trash folder and compacting your mail folders and then try again." I did all of that, even went into windows disk cleanup to free up more disk space. I get the same error message. I have 3 email accounts in Thunderbird, only one account has this problem. When I use Outlook express I do not get any error messages but I do get a malicious email that AVG intercepts. So how can I purge bad email from Thunderbird ? Or what else may be going on and what else could I try ? I have deleted all old emails, in Thunderbird, I routinely delete old emails. Thanks alot Sam

Hi. I´m running thunderbird 150.0 under win10 an a HP2760p with 8 GB RAM and 155 GB of free SDD-space.

I´ve got the errormessage: "Nachrichten konnten nicht in die Mailbox-Datei geschrieben werden. Stellen Sie sicher, dass das Dateisystem Ihnen Schreibrechte einräumt und genügend Speicherplatz zur Verfügung steht, um die Mailbox zu kopieren."

That is: Unable to write mesages to the mailbox-file. Make shure to have writing rights according to the filesystem and enaugh space is available to copy the mailbox.

I can´t find a limitation to filesize. I deleted a lot of mails, the error persists. I updated from thunderbird 140 to 150.0. The error persists. I downloaded my emails on an win11 Laptop. The download stopped after a while with the same error.

What can I do ? Thanks in advance - Robin

I get the following message when I try to download emails "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

How to connect email account!? I have been tring for days to set up email account incoming server settins accept but outgoing page despite green ticks will not let me finish, I am 80 and do not understand why I am being blocked when allsettings have green ticks??

I'm using Thunderbird 152.0a1 (2026-04-22) on Windows 10 64 bit. When I click the "Get Messages" button or File > Get New Messages for > [my e-mail account] nothing happens. The only way I've found to check for messages manually is by closing and re-opening the program.

I run a rowing club with membership near 200 members. If we can not successfully use mailing lists, I am only left with the option of sending out individual email to each person. I'd like to know why I'm not receiving error messages when nothing is being delivered. I can send out email to one addressee, but not to a group.

Each time I open Thunderbird, it redownloads 423 gmail messages. When I exit, and relaunch, it repeats this. I also get an error message. It's been doing this for a week or so, but never up till then.

I've checked my settings, redone the saved password so it's now Oath2 and am out of ideas.

Can you help?

I keep getting emails like the one below. How can I stop Proofpoint from blocking emails like this? I can't get any response from Proofpoint.

Thank you.

Subject: Mail delivery failed: returning message to sender Date: Mon, 23 Mar 2026 15:32:49 -0400 From: Mail Delivery System <Mailer-Daemon@server240.web-hosting.com> To: [edited]@unexpectedwildliferefuge.org

This message was created automatically by mail delivery software.

A message that you sent could not be delivered to one or more of its recipients. This is a permanent error. The following address(es) failed:

[edited]@marshallsterling.com host mxb-00261401.gslb.pphosted.com [148.163.148.189] SMTP error from remote mail server after initial connection: 554 Blocked - see https://ipcheck.proofpoint.com/?ip=66.29.141.68

I have installed Mozilla ThunderBird Previously on many machines. Am Familiar with Incoming Email Servers and OutGoing Email Servers ... Also special ports ... POP ... and .... SMTP ... IMAP ... ETC ... GBGB On this Machine ... Dell Latitude ... 128 GB SSD ... 8GB RAM I have Mozilla ThunderBird Installed for as Single Email Account ... OverstreetENGR@Juno.com

When I REPLY to Emails , THIS IS the error message that I get : Sending of the message failed. The message could not be sent because the connection to Outgoing server (SMTP) smtp.juno.com timed out. Try again.

error message follows

sending message failed.

An error occurred while sending mail. The mail server responded: Authentication required please verify that your email address is correct in your account settings and try again.

The email address is correct. What is going on?

As of today, Thunderbird will not make contact with my servers and won't download emails. i had been having some issues with Thunderbird not sending emails last week. Plus, Firefox won't connect with my internet provider's website so I cannot access emails thru webmail. Firefox either times out or says connection could not be made. Could there be an issue within account settings?

2 mails n’apparaissent pas dans la boite de réception, mais ils sont dans "tous les mails" de ma boite "Pro" (Google) Je les ai envoyé depuis ma boite perso ( Free), ils ne figurent pas dans les envois, je les trouve en faisant une recherche, mais sans savoir s'ils ont été envoyés .. Et dans la recherche je trouve plusieurs fois le même mail, l'adresse n'était pas bonne (???), je ne sais pas s'ils ont été envoyés plusieurs fois ... ce qui n'est pas agréable pour la personne qui reçoit!!! Merci de votre aide! Olivier

I have 5 email accounts in Thunderbird. After the update to 148.0, any incoming email gets duplicated into all five email inboxes. Also, Thunderbird re-downloads the various email folders (e.g., spam) repeatedly. How do I make this stop?