Thunderbird Community Forum

For about a week now I have been unable to send emails. Receiving them is fine. 1 had just said yes to the latest update. When I try to send I get this message - Sending of the message failed. An error occurred while sending mail. The mail server responded: Service unavailable; Client host [125.214.85.178] blocked using b.barracudacentral.org; http://www.barracudanetworks.com/reputation/?pr=1&ip=125.214.85.178. Please check the message recipient "reply-fe9515767360017975-18_HTML-75443594-7238404-12125@emails.avg.com" and try again.

I am 71, not technologically minded but am rather frustrated by this.

I hope you can help me out.

Thank you

Rita

When I try to send a message I get the following error message: An error occurred while sending mail: Outgoing server(SMTP) error. The server responded: Cannot connect to SMTP server 209.71.208.9 (209.71.208.9.25) connect error10060 How do I fix this?

I cannot send messages from any of my accounts after migrating to Greenby. I have tried to setup their outgoing server as per their instructions but it does not work. They have a AI tool which I keep going round and round in cycles

We use Thunderbird because of its flexibility across multiple OS and interfaces. We have only one PC using Windows, and that is a Microsoft surface running Windows 11. On that machine, emails are, from time to time, delayed, sometimes by 12 hours or more.

The emails come through normally on Android and Linux machines, and we had no difficulty on the Surface until we upgraded it from Win10 to Win10. The emails can also readily be accessed using a web interface to the provider's Apache server. Meanwhile, asking Thunderbird to get emails consistently reports "No new emails".

This is a very intermittent problem, with no discernable pattern to when it happens, or how long the messages get delayed.

Can anyone give me some pointers on where to start troubleshooting this?

I have been using Duck for email etc. Suddenly I can not send outbound emails. Contacted Spectrum and was informed that Microsoft, Google, and Apple have suspended cooperation with spectrum. Because of this situation, Duck can not send emails etc. What can Mozilla do to rectify this situation and when? Mozilla is a great product. Thank you Jeff Herriman

Assistance with Read Receipt and Delivery Status Notification

Good afternoon,

Thank you for taking the time to read my email.

I have been trying to determine why I do not receive read receipts after selecting Return Receipt and Delivery Status Notification under the Options tab when sending emails. This has been an ongoing issue for more than 10 years.

I am currently using Thunderbird version 152.0 on one computer and 140.10.2 ESR (32-bit) on another. Despite trying numerous settings and troubleshooting steps over the years, I have never been able to receive a read receipt.

I would be truly grateful if you could guide me in the right direction or let me know if there is a setting I may have overlooked. If there are any troubleshooting steps or additional information you need from me, I would be happy to provide it.

Thank you very much for your time and assistance. I sincerely appreciate your help.

Kind regards,

Brenda

I finished building my Linux PC yesterday. I got Linux Mint, all that good stuff. But when I try to log into Thunderbird Mail with my iCloud account, it says it's in the database and I select IMAP and then it says "Unable to log in at server. Probably wrong configuration, username or password."

Hi, I've used Mozilla Thunderbird for years to import all my Tiscali (talktalk) emails with no problems.

Now, I can’t get any emails as the server settings have changed.

What server settings do I now need to get my system working again?

I use Thunderbird with my Jubii mail and lately, every time I try to send an email, Thunderbird wants my password to my email address in order to send he mail. How do I make it so that I won't have to reenter my password every time I send an email?

After several years of working perfectly,For no reason, I am getting this message when trying to connect to Xfinity email server

"  Login to server mail.Comcast.net with username t_m_f@comcast.net failed."

I have set all Comcast server settings to the default. Going directly to Xfinity email works great . So it must be something wrong with Tbird. I also uninstalled & reinstalled Tbird. This is frustrating !!!!!!

I hope you all are well!

I´ve been having a problem with thunderbird for a while now and today took the time to do the troubleshoot and checked all the account settings. no firewall, no add ons Researching the problem i came across the incompability of different TLS standards. Apparently when thunderbird updated to 78.0 in 2020 a lot of people had the same problem and solved it by downgrading . Since this problem came on suddenly, possibly when thunderbird upgraded automatically, and it only applys to select emails (about half) I guess different TLS standards, some of which are no longer supported by thunderbird, are the reason for this. If i log in to my mailaccount I can see all the emails, same goes for my mobile devices. That´s how i know thunderbird doesn´t display all the messages. My question: Did anyone else encounter this problem? Did I analize this correctly or did I overlook something? I don´t want to change to another provider. I always liked thunderbird for being simple and clean. But downgrading won´t be a sustainable solution either I guess. Thanx for your help. Have a nice day.

The email I thought I’d sent isn’t in my sent folder. I saw it being sent. I also tried restoring the sent items folder, but it didn’t work. What should I do? Is there any risk of it being misused?

Returned from a 1-month trip and my Windows11 would load - repair didn't fix it, so I had to reload Windows.

Now I'm unable to right-click on a photo and send it via my Thunderbird email. When I right-click on 'Send to', there's no email option showing.

Thanks in advance,

Scott

When I try to access my e-mails I am getting message." Login to server pop.tiscali.co.uk with username [redacted]@tiscali.co.uk failed." Nothing I do helps

Good morning. We have McAfee Ultimate with email scam protection. Our "att.net" email was hack 2 weeks ago. We have changed "att.net" passwords. We began to again receive emails. on 6/14/26 we began receiving this message when trying to down load 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" We deleted emails found in the McAfee Alert mail box. We deleted the "att.net" email from McAfee and then reconnected it. we have gmail accounts and deleted trash. any thoughts for how to correct will be appreciated. jimw