TB hangs looking up IMAP server

TB is hanging on startup as it cannot connect to an IMAP server (Ping times out) I am chasing this separately. If I click on the TB window it grays out and I have to shut… (read more)

TB is hanging on startup as it cannot connect to an IMAP server (Ping times out) I am chasing this separately. If I click on the TB window it grays out and I have to shut TB. I know which account is causing the problem but how can I start TB WITHOUT it trying to access servers so I can delete the problem account?? Thanks in advance. Paul N

Open

*.msf ist not restored

I have a proper profile stored in an backup and 1 *.msf wasn´t restored on the new computer, but it is needed as soon as possible. My tries to restore it wasn´t successfu… (read more)

I have a proper profile stored in an backup and 1 *.msf wasn´t restored on the new computer, but it is needed as soon as possible. My tries to restore it wasn´t successfull, there are no needed things to restore. The needed msf is located in the new profile, and I can´t see the item. Therefore I need help for restoring this particular *.msf. Greets The Texman aka K.-P. Aldag

Open

Unable to write the email to the mailbox - can't pop download emails from gmail

I'm getting a popup error message saying "Unable to write the email to the mailbox" on one of my gmail accounts. This has happened a few times before and I'm not sure ho… (read more)

I'm getting a popup error message saying "Unable to write the email to the mailbox" on one of my gmail accounts. This has happened a few times before and I'm not sure how I managed to get it working again those times, seems hit-or-miss. I've compacted and run a repair on the inbox folder several times as suggested by others. I've updated and restarted Thunderbird and even updated windows and restarted more than once.

Windows 11 Pro Thunderbird 158.0 (64 bit)

I'm attaching a screenshot from the Error Console (Tools -> Developer Tools -> Error Console)

Open 1

cannot get into my email accoint at all

As of Oct 12 2026 I also have this issue. About a week before the 12th I was getting messages that I needed to sign into my RCN account which I would do and it just kept … (read more)

As of Oct 12 2026 I also have this issue. About a week before the 12th I was getting messages that I needed to sign into my RCN account which I would do and it just kept asking me. A few times each night to start then right before it shut me out I had over 50 of these messages just flooding my screen. I never did get a screen shot of that message, but did for the 2 error messages I got later once it shut me out. I shut down my computer the night of the 11th then when I signed back in on the 12th I could not send or recieve any emails. SOmething similar had happened before, but when I shut down again it went away. This time it did not. I then tried to access my emails thru the webmail I can access, but that also had shut me out. I also tried my tablet, a borrowed smart phone, but I could not access anything for my emails. I troubleshooted with my email company and my internet company, but they found nothing. Then I shut off the wi-fi on the smart phone and bin go I could access the webmail. But I still cannot find anything on what to do to fix this. I use RCN for my email, Spectrum for my internet. It is a POP3. Running Thunderbird version 153.5 Oesr (32 bit) Meadow, which says it is up to date. I have norton 360 anti virus & do not use VPN. I disabled my Auto-protect and firewall on the Norton and that did not change anything. I have sent the error messages to RCN and also troubleshot with Microsoft and had some hints, but nothing has come of that yet. Here are the screen shots of the only 2 things I ould capture. The error message was when I was trying to access my email thru Thunderbird. And it came up every time I tried to send messages, not that does not show up anymore and nothing happens when I try and send anything. The second one was when I was trying to access the RCN webmail and it would not let me in on anything I used. Until I shout off the WI-Fi. Then the smart phone could access my webmail account.

Open 1

Thunderbird 153: fresh profiles become partially unusable after some time; Settings and address autocomplete stop working

I was referred here from Thunderbird Bugzilla report 2081665. We are experiencing a recurring problem with Thunderbird 153 on several Windows workstations in a business e… (read more)

I was referred here from Thunderbird Bugzilla report 2081665.

We are experiencing a recurring problem with Thunderbird 153 on several Windows workstations in a business environment.

The important point is that the problem also occurs with completely new Thunderbird profiles created from scratch. It is not limited to migrated or old profiles.

On one workstation this has already happened to three separate Thunderbird profiles.

Typical sequence:

1. Thunderbird 153 is installed. 2. A completely new profile is created. 3. Mail accounts are configured manually. 4. Everything initially works normally. 5. After some time the profile begins to malfunction. 6. Thunderbird Settings no longer open/respond. 7. The address books still exist, but address autocomplete when composing a new message stops working. 8. Creating another new profile temporarily fixes the problem, but the same behavior can return later.

Troubleshooting already performed:

- Troubleshoot Mode - extensions disabled - tested without the existing prefs.js - rebuilt Thunderbird caches and profile UI state - recreated indexes/databases - completely removed Thunderbird from Program Files, AppData\Roaming and AppData\Local - clean Thunderbird installation - clean profile created from scratch - Thunderbird executable and profile paths added to Kaspersky Endpoint Security trusted applications/exclusions

Removing prefs.js from an already affected profile did not restore the Settings window.

A clean test profile initially works correctly.

We have also encountered this behavior on other workstations. Some users have more than 100 message filters and many folders, so rebuilding profiles repeatedly causes significant administrative work.

Several affected computers had Windows user accounts renamed in the past.

We also experienced a separate issue where the Attach File dialog stopped appearing while drag-and-drop still worked. Bugzilla identified this as the already known Bug 2077590, so I consider that a separate issue.

For comparison, after completely cleaning Thunderbird from an affected workstation and installing Thunderbird 115.3.1 with a clean profile, the same workstation currently works normally.

Because freshly created Thunderbird 153 profiles can later develop the same problem again, simply recreating the profile does not appear to be a permanent solution.

Environment:

- Windows workstations - Thunderbird 153 ESR - Kaspersky Endpoint Security - multiple IMAP accounts - business environment

What diagnostic information should I collect from the next affected profile before replacing it?

I can provide:

- Thunderbird Troubleshooting Information - Error Console output - profile file names/sizes/timestamps - Windows Event Viewer logs - sanitized prefs.js - comparison with a working fresh profile

Bugzilla report: 2081665 Known separate attachment bug: 2077590

Open

misconversion (mojibake) of some mails in Japanese

misconversion (mojibake) does not happen when a mail header is as below. Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: base64 misconve… (read more)

misconversion (mojibake) does not happen when a mail header is as below. Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: base64

misconversion (mojibake) happens when a mail header is as below. Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit

It seems encoding in my Thunderbird does not match 8bit. Several years ago Thunderbird had an option to modify text encoding but I cannot find such an option in the recent versions. It would be really appreciated if anyone help. Thank you.

Open 2 1

Having trouble getting into Thunderbird

Haven't been able to get into Thunderbird since 9/26/26, every time I try it keeps asking me for my password. I key it in and it does the same thing. I have had someone t… (read more)

Haven't been able to get into Thunderbird since 9/26/26, every time I try it keeps asking me for my password. I key it in and it does the same thing. I have had someone to come up and look at it, but they weren't familiar with thunderbird, I have been having to use Kinetic email, don't like it. hate gmail.

Open 2 2

An odd request

I received an email from Thunderbird (my email provider) wanting me to join the Early Bird Beta but their link to pay with PayPal didn't work so they requested I add a ne… (read more)

I received an email from Thunderbird (my email provider) wanting me to join the Early Bird Beta but their link to pay with PayPal didn't work so they requested I add a new credit card. I use PayPal often so I know my card on file with PayPal is OK. Seemed odd to me for their request. I could forward their email to me if needed. Looks like they are using Paddle.com Market Limited.

Open 2

Thunderbird and GMail Account Problems

I was using Thunderbird 153.4.0esr 64-bit and my send feature on GMail stopped working. It just spun and spun with no connection. So, I removed the GMail account from my … (read more)

I was using Thunderbird 153.4.0esr 64-bit and my send feature on GMail stopped working. It just spun and spun with no connection.

So, I removed the GMail account from my accounts list and then tried re-adding it, but only received the following error (see image attached). This implies what? I have an account at GMail already? I have a remnant of the previous working account in my configuration? It was working fine until today.

I'm using the automatically derived ports (993 inbound and 465 outbound). That error message appears immediately after having clicked the "Continue" button.

System:

 Kernel: 6.8.0-147-generic arch: x86_64 bits: 64 compiler: gcc v: 13.3.0 clocksource: tsc
 Desktop: Xfce v: 4.18.1 tk: Gtk v: 3.24.41 wm: xfwm4 v: 4.18.0 with: xfce4-panel
   tools: light-locker vt: 7 dm: LightDM v: 1.30.0 Distro: Linux Mint 22.2 Zara
   base: Ubuntu 24.04 noble
Open 1 1

time in thunderbird incorrect

Hi I am at my wits end here - The date in my Thunderbird is behind by 1 hour. This is affecting sent messages and also received messages. This just started today. For ov… (read more)

Hi I am at my wits end here - The date in my Thunderbird is behind by 1 hour. This is affecting sent messages and also received messages.

This just started today. For over a year, the time has been correct. I have not changed any settings in Thunderbird prior to this issue.

My Win11 computer shows the date and time correctly.

I had a Win11 update yesterday. Not sure if that has affected Thunderbird (My province - Manitoba Canada - also stopped using daylight time changes in the last couple of months.) We are now permanently CDT, and is UTC/GMT -5 - which is what it shows in my Win11 setting.

My timezone and time in Win11 settings shows correctly.

Just to see if it would make a difference - In Win11 settings->Time & Language - I changed the time zone automatic to off (even tho the time zone showed correctly) and set it manually to UTC-5:00 Manitoba, - I changed 'Set Time automatically' to off, set the time manually and synced the time.

No difference with Thunderbird.

Why is my time off in Thunderbird?, and what can I do or check to fix this?

Solved 2

Vanishing emails

Recently I updated Thunderbird. When it rebooted, all my emails in the INBOX and ARCHIVED folders were gone. I have tried the usual solutions, including REPAIR FOLDER but… (read more)

Recently I updated Thunderbird. When it rebooted, all my emails in the INBOX and ARCHIVED folders were gone. I have tried the usual solutions, including REPAIR FOLDER buttons. Those archived messages were important. Any chance of finding them?

Open 3 1

Thunderbird 158.0 Could not edit appointments - OSX fix?

Was unable to edit appointments attempts placed a previously unknown dialog box. Search for info found one person advised Select Calendar (tab), edit, calendar properties… (read more)

Was unable to edit appointments attempts placed a previously unknown dialog box. Search for info found one person advised Select Calendar (tab), edit, calendar properties and uncheck the read only box.

In my case the box was already unchecked, checked it, tried it, same result. Unchecked it, tried it same result (not able to edit).

Next I thought maybe some data location is not being changed. So I closed all files, shut down (not a restart) my machine, and restarted it. Opened Thunderbird and tried to change an appointment, did not work. Went to Calendar (tab), edit, calendar properties and found the read only box checked. Unchecked and all seems back to normal operations now.

Open

problem with double entries in the sent folder

When i send an email , it goes to the destination email address all right, but the problem is that it creates two identical entries in my local "sent" folder. As if i ha… (read more)

When i send an email , it goes to the destination email address all right, but the problem is that it creates two identical entries in my local "sent" folder. As if i had sent the email msg two times. This happens only with my hotmail.com account. All of my other accounts (gmail, yahoo etc) dont have this problem. I am using a windows 11 laptop, and both my windows and Tunderbird are fully updated.

Open

Unable to attach files to emails since 30 Sept update (bug2077590)

Since the Thunderbird update of 30 Sept the ability to attached files to my emails has 'vanished'. I press the attach 'button' but there is no response. Never had this as… (read more)

Since the Thunderbird update of 30 Sept the ability to attached files to my emails has 'vanished'. I press the attach 'button' but there is no response. Never had this as a problem before. I am running Windows 11 home version. Help!

Solved 9 9 20

I cannot open Thunderbird on my laptop because it asks for a password from my defunct BlueHost account.

I keep getting the following (see attached image) when I try to open my Thunderbird. I tried to unsuccessfully open safe mode because it still asks for a password from my… (read more)

I keep getting the following (see attached image) when I try to open my Thunderbird. I tried to unsuccessfully open safe mode because it still asks for a password from my very old BlueHost account. I previously worked with AI on this and deleted all BlueHost lines I could find in my account. View the image I have included and see all the messages that include BlueHost. They must be hiding somewhere in Thunderbird. I am not sure what version I have because I cannot open it. Please help! I be happy to send you my phone number is needed.

Open 1

Issue migrating to Graph API

Hello, I'm moving to Graph from EWS and have followed the instructions at: https://support.mozilla.org/en-US/kb/microsoft-ews-graph-migration I get through to screen that… (read more)

Hello,

I'm moving to Graph from EWS and have followed the instructions at: https://support.mozilla.org/en-US/kb/microsoft-ews-graph-migration

I get through to screen that offers Graph API as an option, alongside IMAP, POP3 etc, and click on Graph API which directs me to my browser to log in to my email service (via GoDaddy). I log in successfully which takes me to the Thunderbird 'You're All Set' screen saying the account has been securely connected to Thunderbird and therefore ok to close that screen.

Back on Thunderbird it then progresses but returns with "Authentication Error - unable to log in at server. Probably wrong configuration, username or password".

The username and password are correct, and there aren't any other options available when editing/manually configuring the connection...so at a dead end, alas.

Any pointers much appreciated!

Open 4 2

Time Zone Not Properly Saved when editing Address Book Contacts

When editing a contact in Address Book, after selecting a time zone from the drop down menu and saving the contact, only the first 7 characters of the time zone string ar… (read more)

When editing a contact in Address Book, after selecting a time zone from the drop down menu and saving the contact, only the first 7 characters of the time zone string are displayed in the contact view. When reopening the contact for editing, the time zone field is shown as empty again.

Open 1

How do I recuperate old emails

I swap computers about 3 times in year, and not all of mine emails seen to have transfer. I was wondering if there is any way I could potentially recuperate those emails.… (read more)

I swap computers about 3 times in year, and not all of mine emails seen to have transfer. I was wondering if there is any way I could potentially recuperate those emails.

Open