Bugzilla

(In reply to Ben Bucksch (:BenB) from comment #4)
> Actually, while the send is hanging, I see on the error console:
> ```
> 15:51:58.857 mailnews.smtp: NetworkTimeoutError: a Network error occurred SmtpClient.jsm:442:17
>     _onError resource:///modules/SmtpClient.jsm:442
> ```
> 
> This is strange, because the SMTP server is on my local network.
> 
> Also, the emails do seem to arrive in most cases, because people reply to them, and I see the replies. But the sent process is hanging without error message, no Sent copy is saved, and even "Save" (after "Cancel") doesn't work. So, if the SMTP server is really timing out, why do emails arrive?

This is probably a known issue that occurs due to "connection reuse" when sending emails. When you send one email and it goes out OK, TB keeps the connection open in case there is another messages to be sent. If no more messages are sent, eventually (maybe after 30 seconds or so) the smtp server times out the connection and you see the console error. I have a patch in work to fix this by sending QUIT after the connection is idle for 5 seconds. This will avoid the timeout response from smtp server that you are seeing and has also been reported in bug 1864924.
> 
> At the very least, the bug is that the error from the SMTP client is not forwarded to the frontend and to the end user, and the process is hanging. Even if it was a problem with the SMTP server (which I am not sure is true), it would still be a bug in the error hanging.

Problems with saving the sent message were a know issue but I thought it was resolved back at  bug 1745130. So not sure why you would just recently be having problems saving the sent message to Sent folder or Inbox since I think that patch has been in ESR quite a while.

If you are using IMAP and their really is a failure to access the imap server to save the sent message, the "Save" button will cause the message to be saved into Local Folders. Are you using imap and seeing that?

(In reply to Ben Bucksch (:BenB) from comment #4)
> Actually, while the send is hanging, I see on the error console:
> ```
> 15:51:58.857 mailnews.smtp: NetworkTimeoutError: a Network error occurred SmtpClient.jsm:442:17
>     _onError resource:///modules/SmtpClient.jsm:442
> ```
> 
> This is strange, because the SMTP server is on my local network.
> 
> Also, the emails do seem to arrive in most cases, because people reply to them, and I see the replies. But the sent process is hanging without error message, no Sent copy is saved, and even "Save" (after "Cancel") doesn't work. So, if the SMTP server is really timing out, why do emails arrive?

This is probably a known issue that occurs due to "connection reuse" when sending emails. When you send one email and it goes out OK, TB keeps the connection open in case there is another messages to be sent. If no more messages are sent, eventually (maybe after 30 seconds or so) the smtp server times out the connection and you see the console error. I have a patch in work to fix this by sending QUIT after the connection is idle for 5 seconds. This will avoid the timeout response from smtp server that you are seeing and has also been reported in bug 1864924.
> 
> At the very least, the bug is that the error from the SMTP client is not forwarded to the frontend and to the end user, and the process is hanging. Even if it was a problem with the SMTP server (which I am not sure is true), it would still be a bug in the error hanging.

Problems with saving the sent message were a know issue but I thought it was resolved back at  bug 1745130. So not sure why you would just recently be having problems saving the sent message to Sent folder or Inbox since I think that patch has been in ESR quite a while.

If you are using IMAP and their really is a failure to access the imap server to save the sent message, the "Save" button will cause the message to be saved into Local Folders. Are you using imap and seeing that? (Edit: re-read above, yes you are using imap.)