Hello

turn on debugging by going to settings / General / (button) Config Editor, set mailnews.smtp.loglevel to All then try to send mail, and after failure goto Tools / Developer tools / Error console and copy / paste the content here. Remove identifying information before pasting if necessary.

Dear GP, here it is:

This page is in Quirks Mode. Page layout may be impacted. For Standards Mode use “”. MimeMessageUtils.jsm:148:23 mailnews.smtp: Sending message <8b04a845-6070-fbaf-e072-86c4b50b696c@unipi.it> SmtpService.jsm:85:18 mailnews.smtp: Connecting to smtp://submission.unipi.it:587 SmtpClient.jsm:118:17 mailnews.smtp: Connected SmtpClient.jsm:386:17 mailnews.smtp: S: 220 submission.unipi.it Microsoft ESMTP MAIL Service ready at Tue, 15 Nov 2022 10:20:33 +0100

SmtpClient.jsm:412:17 mailnews.smtp: C: EHLO [172.20.10.3] SmtpClient.jsm:589:19 mailnews.smtp: S: 250-submission.unipi.it Hello [131.114.72.205]

250-SIZE 37748736

250-PIPELINING

250-DSN

250-ENHANCEDSTATUSCODES

250-STARTTLS

250-AUTH GSSAPI NTLM

250-8BITMIME

250-BINARYMIME

250 CHUNKING

SmtpClient.jsm:412:17 mailnews.smtp: C: STARTTLS SmtpClient.jsm:589:19 mailnews.smtp: S: 220 2.0.0 SMTP server ready

SmtpClient.jsm:412:17 mailnews.smtp: C: EHLO [172.20.10.3] SmtpClient.jsm:589:19 mailnews.smtp: error { target: TCPSocket, isTrusted: true, name: "NetworkInterruptError", message: "Network", errorCode: 2152398919, srcElement: TCPSocket, currentTarget: TCPSocket, eventPhase: 2, bubbles: false, cancelable: false, … } SmtpClient.jsm:433:17 mailnews.smtp: Failed to send "QUIT" because socket state is closed SmtpClient.jsm:578:19 mailnews.smtp: Closing connection... SmtpClient.jsm:152:17 mailnews.send: Sending failed; The message could not be sent because the connection to Outgoing server (SMTP) submission.unipi.it was lost in the middle of the transaction. Try again., exitCode=2153066799, originalMsgURI= MessageSend.jsm:335:27 mailnews.smtp: Socket closed. SmtpClient.jsm:497:17

​

Thanks, Chiara

Hello

the server seems to expect (only) an authentication with Microsoft credentials (AUTH line does not include 'LOGIN'). Maybe the thing is configured to allow basic auth only when connected through the Internet, in such case it could (possibly) work with a VPN. Otherwise you could try the OWL add-on, but it's a paid on after one month I think. I guess that if it's an Exchange server it's still possible to setup it to enable basic auth on the receive connector. I have no idea if it's possible at all to use OAUTH with an internal Exchange server.

Thank you for the feedback. I have started a VPN and tried. But it still does not work. I send you the log in case you can understand something... Thank you. Best regards, Chiara

NS_ERROR_FAILURE: Component returned failure code: 0x80004005 (NS_ERROR_FAILURE) [nsIAutoCompleteInput.popup] LoginManagerChild.jsm:250 Element.releaseCapture() is deprecated. Use Element.releasePointerCapture() instead. For more help https://developer.mozilla.org/docs/Web/API/Element/releasePointerCapture menupopup.js:169:13 This page is in Quirks Mode. Page layout may be impacted. For Standards Mode use “”. MimeMessageUtils.jsm:148:23 mailnews.smtp: Sending message <85625fba-1e60-49b8-7007-13e7770c24b5@unipi.it> SmtpService.jsm:85:18 mailnews.smtp: Connecting to smtp://submission.unipi.it:587 SmtpClient.jsm:118:17 mailnews.smtp: Connected SmtpClient.jsm:386:17 mailnews.smtp: S: 220 submission.unipi.it Microsoft ESMTP MAIL Service ready at Tue, 15 Nov 2022 16:49:53 +0100

SmtpClient.jsm:412:17 mailnews.smtp: C: EHLO [192.168.207.59] SmtpClient.jsm:589:19 mailnews.smtp: S: 250-submission.unipi.it Hello [131.114.72.205]

250-SIZE 37748736

250-PIPELINING

250-DSN

250-ENHANCEDSTATUSCODES

250-STARTTLS

250-AUTH GSSAPI NTLM

250-8BITMIME

250-BINARYMIME

250 CHUNKING

SmtpClient.jsm:412:17 mailnews.smtp: C: STARTTLS SmtpClient.jsm:589:19 mailnews.smtp: S: 220 2.0.0 SMTP server ready

SmtpClient.jsm:412:17 mailnews.smtp: C: EHLO [192.168.207.59] SmtpClient.jsm:589:19 mailnews.smtp: error { target: TCPSocket, isTrusted: true, name: "NetworkInterruptError", message: "Network", errorCode: 2152398919, srcElement: TCPSocket, currentTarget: TCPSocket, eventPhase: 2, bubbles: false, cancelable: false, … } SmtpClient.jsm:433:17 mailnews.smtp: Failed to send "QUIT" because socket state is closed SmtpClient.jsm:578:19 mailnews.smtp: Closing connection... SmtpClient.jsm:152:17 mailnews.send: Sending failed; The message could not be sent because the connection to Outgoing server (SMTP) submission.unipi.it was lost in the middle of the transaction. Try again., exitCode=2153066799, originalMsgURI= MessageSend.jsm:335:27 mailnews.smtp: Socket closed. SmtpClient.jsm:497:17 This site uses a deprecated version of TLS. Please upgrade to TLS 1.2 or 1.3. 20221101185644 STATE_IS_BROKEN without a known reason. Full state was: 1

could you have a software firewall on your computer ? a hardware firewall should have been worked around by the VPN, but not if the problem is in your computer...

Dear GP, I have checked and I do not have any sw firewall. Any other ideas ? Thank you, Chiara

It's a system problem all right, TLS connection seems to trigger something bad. I have tried to create a connection to your mail server, obviously it can't succeed since I don't have a login, however it get further, until trying the authentication. I understand now why the AUTH does not specify LOGIN, it's logical since LOGIN passes the password in clear so it's not possible to send it before the link is protected (secured by ciphering) with TLS (STARTTLS) - in my test after the successful TLS exchange, the server capabilities are sent again and this time I get 250-AUTH GSSAPI NTLM LOGIN

Can you try to start Thunderbird in troubleshoot mode, try again. If it fails too, while in troubleshoot mode, create another send smtp mail with the parameters smtp.unipi.it, port 587, STARTTLS and normal password, set it as default for your account and try again to send a mail ? if it fails, try to change port to 465 and replace STARTTLS by SSL/TLS and try again.

... or there is also the sledgehammer way. You can find on the internet (youtube) a tutorial to install openssl on a mac. Search on 'Install openssl on Mac OSX - Mac App Store' and you will find it on a site called macappstore . org. I'm not linking to it because any link posted here is adding a very long delay to get the post displayed (approved ?).

When you have openssl installed, in a terminal enter

openssl s_client -crlf -starttls smtp -connect submission.unipi.it:587

if the server displays a dozen of lines of goo beginning by something like

depth=2 C = US, ST = New Jersey, L = Jersey City, O = The USERTRUST Network, CN = USERTrust RSA Certification Authority

then type in:

EHLO aa

(type enter here)

if you get something like

250-submission.unipi.it Hello ... followed by 8 or 9 lines of commands (among them 'AUTH') your system is good and it's thunderbird that has a bug.

Good Morning ! I have tried this one: end smtp mail with the parameters smtp.unipi.it, port 587, STARTTLS and normal password, set it as default for your account and try again to send a mail ?

and it works !!!!! Super duper. I guess I need to check if using this other server has problems. Thank you so much !

I may as well write an epilogue to this story. Who ever will read it, I have no idea.

The server submission at unipi.it is a Microsoft server - probably the smtp connector of the Exchange server driving all the game. The server smtp at unipi.it is a Linux server - announcing itself as Postfix.

Trying out these servers with openssl show the use of the '-crlf' option of openssl s_client; from man openssl-s_client: This option translated a line feed from the terminal into CR+LF as required by some servers.

It turns out that 'some servers' are very probably Microsoft servers.

In short, if s_client is used without the -crlf option, it hangs after the Tls exchange - there is no way to enter 'EHLO xxxx', while it works with the Linux server. Same happens vs respectively the Google server (smtp at gmail.com) and the Microsoft server (smtp at office365.com).

I took a wild stab at the idea that smtp at unipi.it could work as well as the official server and it turned out right by some stroke of luck.

But the fact that Thunderbird has exactly the same symptom as openssl s_client is suspicious. I wonder if there is a relation between the 2 problems.

To the original poster: if ever you read this and reply, please mark a post a solution to avoid this keeping unresolved.

Thank you very much again also for the explanation ! If you look at this again and have time ... since the server submission.unipi.it was indeed working and suddenly started to present the problem do you think something changed in the configuration of the server ? Or maybe something changed in Thunderbird with an automatic update ? Thank you ! Chiara

Unfortunately I don't know. I have tried with the office365 smtp server and my Thunderbird 102.4.2 and there is no such problem, while openssl with the same OS (Ubuntu 22.04) displays a similar problem with office365.

Everything seems to work under Windows but a possibility is that with Windows, the terminal is sending a crlf by itself so no need of the -crlf option with openssl. But the relationship with Thunderbird is distant anyway, since Thunderbird does not use openssl. Since I can't repro reliably with Thunderbird it's difficult to get further (I don't have access to a Mac)

You could possibly ask the Univ IT, but it can be problematic if you are a student and you are not officially allowed to use the alternate smtp server, so be careful with that.