Thunderbird Community Forum

Hello, I have a problem with sending out emails. I can receive them but not send. when I set up an email and click on send, it does the spellcheck then attempts to send it, then a dialogue box comes up with: 'log into server smtp.iprimus.com.au with user name janas_3 failed'. It gives me the options of: Retry, Enter new password or cancel. I have tried using the existing password, and a new one and nothing works. I have contacted my Internet provider, who checked all the account settings, which were correct. Their advice was to contact Thunderbird for support, can you help me please?

Several days ago we inadvertently deleted batches of emails from our two Thunderbird Gmail accounts on our PC and Apple devices. The lost emails were duly recovered but only after having to change my Google password. However one of our Thunderbird Gmail account will not download any new messages coming in. Ultimately we deleted that account from Thunderbird, intending to reinstall it. We deleted the account by pressing the Red button in account settings. We confirmed that messages are received to Gmail's Web page Inbox Now when I attempt to reinstall the account and press Add Account, I get the UNABLE TO LOG IN AT SERVER MESSAGE shown below. The "Your Full Name" I am putting in is the name on the Google account deleted from Thunderbird, and the password I have tried is my new Google password. I have tried the process of not adding in the password until requested to do so but this did not work either. Any suggestions please?

Thunderbird was working fine on my Laptop until yesterday's update. Now I keep getting the above message. There is plenty of desk space and my write privileges haven't changed, If I delete yesterday's messages and try downloading new ones those messages reload. I think my tablet hasn't yet installed the update and is currently loading emails normally. Any help, much appreciated!

The last I was able to send an email from my laptop (W11 Home) was 5 days ago. I've made no changes in Thunderbird (140.6.0esr (64-bit)). I've checked with my ISP (PenTeleData - ptd.net) and all is ok. I checked with Norton (360 deluxe); turned off firewall temporarily and tried to send again. Still getting same message.

I can't send anything. I updated at 3 ish and now it says the following : "Sending of the message failed. The message could not be sent because connecting to Outgoing server (SMTP) promail.ptd.net failed. The server may be unavailable or is refusing SMTP connections. Please verify that your Outgoing server (SMTP) settings are correct and try again."

I can receive, but not send, emails using Thunderbird on my PC. I believe this problem began when Thunderbird was updated on 1/13/26. I have no problems sending email on my tablet.

My service provide does not support TLS 1.2, so I tried changing security.tls.version.min to 1. This did not help.

The attached shows the error message and my SMTP settings (1st image) and my service provider's email server settings. I tried changing the SMTP port to 587, but this resulted in a time out error.

Any help is appreciated, Norm

I can no longer send emails. I can send them through mail web browser and was in touch with their technical support and the problem is not on their end. The message I get when trying to send an email is: "Sending of message failed. The message could not be sent because connecting to outgoing server(SMTP) Promail.ptd.net failed. The server may be unavailable or is refusing STMP connections. Please verify that your outgoing server (STMP) settings are correct and try again". I checked my outgoing server settings and they are correct. I started Thunderbird in Troubleshoot mode and the problem still occurs. I started my Windows 10 in Safe Mode and the problem still occurs.

I have just changed to a new pc. Thunderbird was working fine until Saturday when it stopped sending emails. I have discovered that the username on the outgoing server is missing but there is no method of adding it and I have spent all day trying to find a way, including twice reinstalling Thunderbird which has brought back the same issue each time. Any advice on the web seems to be for older versions.

When I have Thunderbird desktop running but I am focused in another application, I receive a popup notification when a new email is received. In the popup, there is an X to make the notification disappear, but it would be very handy if there was also a trash can icon where, if you clicked on it, the message would be deleted from your inbox without having to go back to the TB app. I didn't see any such options in TB settings, and I have searched the forum to no avail. Is this possible? Thank you.

I used to be able to send an email or forward an email by clicking on "forward" and my address book would show up at the left side of the screen and I could click on the names I wanted to send or forward the note and it would add them to the "send to" of my email so I could send it to multiple people. For some reason that has now stopped and I can only send to one person at a time which is very cumbersome and time consuming. Does anyone know how to solve this problem? I hope I'm describing it right.

Not sure which "topic" best describes my question, so . . . .

OS: Windows 11 Thunderbird 140.1.0esr

I have been using T-bird for several years, and have made to changes to configuration in recent memory. Beginning today, when I try to send an email through my Comcast account, it fails with the following message:

“An error occurred while sending mail: Outgoing server (SMTP) error. The server responded: resomta-h2p-555031.sys.comcast.net resomta-h2p-555031.sys.comcast.net EXMTP server not available.”

The outgoing SMTP server is configured as follows: Outgoing server: smtp.comcast.net Port: 465 Security: SSL/TLS

For comparison, sending email from my Android phone, using the Gmail client with the same server specs, also fails, thought it gives no information.

For more comparison, I configured Outlook to test with it, and it was able to send successfully. I noticed in setting it up that it used the same server name, but with port 587. Armed with that information, I changed the port setting in T-bird to 587. With that change, the send still failed but with a different error:

Sending of the message failed. The message could not be sent because the connection to Outgoing server (SMTP) smtp.comcast.net was lost in the middle of the transaction. Try again.

Any help is appreciated.

I have two email accounts, one is hotmail.com, the other is on outlook.com

The SMTP for the outlook account works fine, but Thunderbird puts that same smtp details into the Hotmail account smtp. That also puts into the Hotmail username, the outlooks email address.

If I try to send an email using the Hotmail account, I get a message saying 'Hotmail can not send using xx@outlook.com

If I use the settings to make the username xxx@hotmail.com, it puts that into the smtp of the outlook.com address then that will not send giving the same fault. This has only started this last couple of days, nothing changed in the settings.

This only occurs on my Desktop. On my laptop with same settings it works fine.

Thunderbird is showing up to date?

Help Gerry

Could anybody help me? Since yesterday morning I have not been able to send or receive emails on Thunderbird.

I have two computers: a laptop and a desktop. On both of them I use Thunderbird as my main email service. On the desktop I also have MS Outlook. I am able to send and receive emails on the desktop on MS Outlook.

Error message on the desktop when I try to send a test email: Sending message failed. The message could not be sent because the Outgoing server (SMTP) mail.rushmore.com failed. The server may be unavailable or refusing SMTP connection. Please verify that your Outgoing server (SMTP) settings are correct and try again.

Error message on the laptop when I try to send a test email: You are about to override how Thunderbird identifies this site. Legitimate banks, stores, and other public sites will not ask you to do this. Location: mail.rushmore.com:587 [get certificate] This site attempts to identify itself with invalid information. Outdated information The certificate is not currently valid. It may have been stolen or lost, and could be used by someone to impersonate this site. [check] [Permanently store exception]

    [Confirm Security Exception] [Cancel]

Interestingly, yesterday I was receiving the same error message on the desktop computer, except the number under Location mail.rushmore.com: was different (not 587). I do not remember what this number was.

My current SMTP server settings: Server name: mail.rushmore.com Port: 465 (Default: 465) Connection security: SSL/TLS Authentication method: Normal password User Name: halina@rushmore.com

Please let me know what I can do about this. Thank you!

Halina Hladysz

Please help me! I have expanded on the information which I sent few days ago.

1. Problem which needs to be solved: Starting on Saturday (Oct 18th) morning I have not been able to send or receive emails on Thunderbird. (I turn down my entire network for the night. On Friday evening, before I turned it down, I was still using Thunderbird without any problems. On Saturday morning, after turning the network up, Thunderbird did not work.)

I have two computers: a laptop and a desktop. On both of them I use Thunderbird for most of my emails. They have Windows 10 operating system. Thunderbird stopped working on both computers and at the same time.

2. MS Outlook still works On the desktop I also have MS Outlook. I am able to send and receive emails on the desktop on MS Outlook. There was no break in this software package working.

3. What happened in my email correspondence prior to this problem For about one week prior to Thunderbird’s stopping to work I received numerous emails – which appeared to be sent from my email address xxx@rushmore.com. These emails were pretending to be sent from various companies, including some warnings about my email which needs to be reconfigured or something like this. I deleted all these emails immediately without clicking on any links they would send. Unfortunately, my email provider (BluePeak company) did not catch these emails; they should had been sent to the SPAM folder on their server.

I suspect that maybe some of these emails, or one of these emails, created this problem. A virus?

I have done a full virus scan and it found no problem.

4. Error messages on the desktop when I try to send a test email:

See attachment number 1 for a screenshot.

When I click on [Cancel] I get this message:

See attachment number 2 for a screenshot.

Sometimes instead of these two error messages, I receive a completely different message: see attachment number 3.

5. Error messages on the laptop when I try to send a test email:

On my laptop the error messages are the same, except the number in the [Location] section is different. 587 on the laptop, 465 on the desktop.

6. My current SMTP server settings: Server name: mail.rushmore.com Port: 465 (Default: 465) Connection security: SSL/TLS Authentication method: Normal password User Name: halina@rushmore.com

Could one of you help me, please? I am completely “frozen” with being able to work on some of my projects; one important is organizing a big event and all my communication (high number of emails by now) are on Thunderbird.

Thank you!

Halina H.

Hi Thunderbird, At the weekend we accidentally completely deleted some Gmail emails from Apple Mail . These were also deleted from Thunderbird (2 Gmail accounts) on our PC. We recovered the emails, in the process having to change my Google Password. Whilst the deleted emails returned, one Thunderbird Gmail account was not receiving new incoming emails. (one account is) The emails are arriving as normal into Gmail. After various unsuccessful attempts to to connect to the server I deleted the defective Gmail account from Thunderbird, using the Red Button in account settings, hoping to then be able to reinstall it as a new account. When I attempt to reinstall the now "deleted" account I get the yellow "Unable to log in at Server" message. . The password I am using to add the account is the same as the one I use to sign into that account on Gmail (set on Monday), but it does not seem to be working on TB. I tried the trick of not putting in the password when setting up the new account but this did not work either. I am using TB 140.6.0esr Any suggestion please John

Dear community members, Since receiving the Thurderbird release 140.4.0esr on Oct 14th, I have not been able to send email from any of my accounts (2xIMAP and 3xoffice365 through OWL). Nothing has changed in the account settings. Receive works ok. The usual easy fixes do not seem to work (restart, firewall switch-off, etc.). Any ideas beyond having to rewind to an earlier version and rebuild the whole thing (hopefully not!)?

Version 140.4.0esr Build ID 20251010020716 User Agent Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:140.0) Gecko/20100101 Thunderbird/140.4.0 OS Darwin 24.6.0 Darwin Kernel Version 24.6.0: Mon Jul 14 11:30:30 PDT 2025; root:xnu-11417.140.69~1/RELEASE_ARM64_T6020

Thank you for your help! Heli

I am using TB 140.7.0esr(64bit) on a windows 11 desktop/ Starting 15 Jan at ~ 8pm, my outgoing SMTP email from multiple tds.net email accounts through my default server (tds.net) is failing with the following message: "Sending of the message failed. An error occurred while sending mail: Outgoing server (SMTP) error. The server responded: Cannot connect to SMTP server 129.159.94.43 (129.159.94.43:587), connect error 10060." The outgoing SMTP configuration is: "Server name: mail.tds.net Port: 587 User name: john.randle Authentication Method: normal password Connection security: STARTTLS" I have not made any changes to that configuration. I am still able to send SMTP by switching to another email account/server (e.g. gmail.com). I have contacted tds.net and they say, not surprisingly, that it is an email client (thunderbird) issue. I am getting the same error on another desktop running windows 10 with TB 140.6.0 esr (32bit). Any suggestions will be appreciated. Thanks in advance.

It seems that after updating to the latest version, Thunderbird is not displaying new emails. The numbers of new emails in the folders are changing, but the emails are not loading. I performed maintenance on the folder, but the emails disappeared and I no longer have any emails in my Inbox. I use IMAP, everything is OK on my phone and on the web. This is happening with Thunderbird at home and at work.

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