I-Thunderbird Community Forum

I can receive outlook e-mail but I cannot send from Thunderbird. I am asked for a password for the specific Microsoft server. I enter my Microsoft account password but this does not work. Security setting is STARTTLS withNormal Password authentification. My other Thunderbird non-MS e-mails are problem free.

Hi. Since the last 2 updates, my Bell sympatico email through T-bird cannot SEND anymore emails (No errors are given but the email never comes through). I can receive emails without issue and when I use another tool (like Outlook or go directly through my browser, the sympatico emails come through) I attached the settings for the SMTP in a screenshot if that could help.

Any idea how to fix this?

Tx, Robert Z.

Hello,

Everything working just fine last night. Wake up and Thunderbird will not retrieve emails.

Remembered this old message I got so I went through and deleted my second email address, didn't help.

https://support.mozilla.org/en-US/kb/thunderbird-and-yahoo

Checked all settings compared to Yahoo, still won't download messages. I can even send a message with my current settings no problem, and it does login, just won't retrieve emails. Gives me a connection timeout.

Anyone have any ideas?

As a die-hard fan of Mozilla products for many years, I genuinely want to say thank you to the Thunderbird team for keeping such an amazing open-source project alive and improving it continuously. Thunderbird is still one of the most trusted and powerful email clients ever made, and many of us truly love using it every single day.

But from the bottom of my heart, there is one feature I strongly feel Thunderbird now urgently needs.

Please give Thunderbird a complete Mozilla Account–based sync system, just like Firefox.

Today, whenever we shift to a new computer, we still have to manually:

• reinstall extensions
• reconfigure settings
• restore filters
• restore signatures
• adjust preferences again
• rebuild our personalized setup

For long-time Thunderbird users, this takes a lot of time and effort.

Firefox already gives us such a beautiful and worry-free experience:

• Install Firefox
• Login with Mozilla Account
• Everything comes back automatically

And honestly… that experience feels magical.

As Thunderbird users, we dream of the same simplicity:

• Install Thunderbird
• Login with Mozilla Account
• Extensions auto-install
• Settings sync automatically
• Filters & signatures restore instantly
• Everything feels exactly like our old computer

No stress. No manual setup. No fear of migration.

This is not just a “feature request.” For many loyal Mozilla users, this would be one of the biggest quality-of-life improvements Thunderbird could ever receive.

The Thunderbird team has already discussed this idea publicly for years, which gives users hope that someday it may finally happen.

Please make Thunderbird truly cloud-connected and worry-free for the next generation of users.

Many of us are not just users of Mozilla products — we are emotionally connected to them. ❤

I've been using Thunderbird for about two months now and I just realized that Thunderbird (150.0.1) seems to be unable (or unwilling) to use some of the fonts that are on the computer (Windows 10, plenty of RAM and disk space).

Let me explain that I don't send a lot of emails, and most of the ones I do send are just a few lines so I had not had any reason to bother with the font -- the default font was fine -- until today...

Today my experience with fonts in Thunderbird was extremely disappointing. It started when I was composing an email and I copied/pasted some text from a web page into the email. Rather than treating the pasted text as simply text to have in the default font, Thunderbird put it in some strange font and size. This might have been Thunderbird's attempt to use the font from the website but neither the font nor the size resembled the text that I had copied/pasted. That was when I noticed that Thunderbird does not let you choose the actual size but only offers the choice to make text larger or smaller. Making the text smaller was sufficient for that particular time.

As I finished the email, I tried to sign my usual signature. Thunderbird lets you choose the font but once I had chosen the font that I routinely use for my signature, I discovered that Thunderbird totally ignores the choice that it just let you make. Instead of displaying the signature in the chosen font, it displayed my signature in a plain sanserif font.

I could live with a limited choice of fonts -- I have used another program where the only choices were serif and sanserif -- but I cannot understand why Thunderbird would offer a font choice menu that includes all my installed fonts when it actually only honors three choices. The only fonts reliably used seem to be some generic sanserif font that Tunderbird calls Helvetica/Ariel, a generic serif font that it calls Times and another serif font it calls Courier.

The dropdown menu lets me choose any of the fonts I have installed, some of them display properly while composing the email, others don't. If I send the email to another of my email addresses, Thunderbird displays the text the same way -- some fonts are correct and some fonts get replaced with one of Thunderbird's generic fonts.

I'd really like to have all my fonts available -- but that doesn't seem to be possible with Thunderbird so I guess I need to figure out which fonts Thunderbird is willing to use.

I have created an account instance in account settings, and the "Test connection to server" says it is OK, but when I go to the mail tab the get messages button and New Message are grayed out an NO accounts are listed in the "folders" area. Not does it ever ask for my password to the SMTP server I have selected. I have an existing account with my own email service (Hover), and MUST connect to that. This is critical, as I need my e-mail to accomplish necessary activities.

With 03.04.2026 they began to notice that the attached emails in eml format (the attached emails have attached documents, mostly pdf) sent from yandex mail stopped opening. Everything used to open well. Eml also does not save to disk. If you send the same files via Gmail, everything opens. Program version 150.0.1

On my PC Thunderbirds sending/receiving mail says the mail server refused my connection. My laptop works fine. I have duplicated my laptops in/out specifications onto the PC but still nothing works. Spectrum says everything on their end is fine but can't vouch for roadrunner who is the rr in my mail address of ca.rr.com. All this started about 4 days ago. Any ideas on what to try next? Thanks.

Hi

When Thunderbird is started maximized it overlap taskbar if is set to hide and taskbar won't show until Thunderbird is minimized and maximized. Another way is to press the Win key two times. Then the hided taskbar can be shown/use. The same thing happens to Firefox. Only when is first started. Then if Firefox is minimized and maximized, press Win key two times, press F11 two times then the hided taskbar show/hide normal.

It is a setting that can be changed to start Thunderbird and Firefox in full screen and do not overlap hided taskbar?

When emails arrive it shows the number received in bold in my inbox. Since the last update instead of the new emails being listed at the top of my inbox they disappear. I then have to search through all the emails listed at the top of my inbox to find out if the new emails have been added to one of those. How do I get back to having all new emails listed at the top of my inbox.

This is a continuation of the thread - [is being managed by your organisation CAUSE: Bitdefender]

The solution of deleting the Registry Key does not work. It simply comes back after reboot. I have engaged with BitDefender support and they suggested the same thing - they also added to uninstall TB which I am not going to do.

The issue is that the BitDefender extension is not installed in a normal way, and cannot be removed. The settings in BitDefender do not make any difference, I cannot change settings in a Thunderbird account eg change a folder location, it looks like it works, but it actually does not.

I did find in the about:config extensions.webextensions.uuids key has the bdThunderbird@bitdefender.com entry but there is no indication as to what other strings belong to the entry and I do not to mess things up.

I do realize this is a BitDefender issue, and i did follow up with their support but I am wondering if anyone has solved this annoying issue.

Thanks

Ever since one of the recent updates, my new email notification box is showing up on wrong monitor. I have a 2 monitor setup, the notification box is now showing up on the second monitor. I have tried turning the option off and back on but makes no difference.

Got new internet provider. Old provider has blocked or frozen me out of my prior email account. I need to see my contact list and provide those people with my new address.

In Thunderbird all of a sudden my sent e-mails are going in to the sent box of ANOTHER e-mail address I have on Thunderbird. I looked at some similar posts and think my settings are correct but obviously not. Please help! Thanks, Adam

I have accidentally opened up hundreds of mail I meant to delete. I cannot access my emails, Thunderbird keeps failing to respond. I have tried closing each tab but I cannot tell what is going on. Help please. I can't give the version as it doesn't respond to any instructions