IMAP Sending Issue with Multiple Accounts

[Serghei Iakovlev]

Hello everyone,

I'm currently working on setting up Gnus for sending emails over IMAP
depending on which email account I'm using. I have two accounts:
ProtonMail and Gmail. Receiving emails works fine for both, but I'm
struggling with sending. Here's the error I encounter in the
*Messages* buffer:


Sending via mail...  gnutls.el: (err=[-15] An unexpected TLS packet
was received.) boot: (:priority NORMAL:%DUMBFW :hostname
smtp.gmail.com :loglevel 0 :min-prime-bits nil :trustfiles
(/etc/ssl/cert.pem) :crlfiles nil :keylist nil :verify-flags nil
:verify-error nil :callbacks nil) gnutls-negotiate: GnuTLS error:
#<process smtpmail>, -15


What I'm aiming to achieve is the ability to send messages, including
responding from Gmail to emails received on Gmail. Here's the
relevant snippet of my configuration:

(setq gnus-secondary-select-methods
      '((nnimap "main"
                (nnimap-address "127.0.0.1")
                (nnimap-server-port 1143)
                (nnimap-stream starttls)
                (nnimap-inbox "INBOX")
                (nnimap-expunge never)
                (nnmail-expiry-wait immediate)
                (nnmail-expiry-target "nnimap+main:Trash"))
        (nnimap "gmail"
                (nnimap-address "imap.gmail.com")
                (nnimap-server-port "imaps")
                (nnimap-stream ssl)
                (nnimap-inbox "INBOX")
                (nnimap-expunge never)
                (nnmail-expiry-wait immediate)
                (nnmail-expiry-target
      "nnimap+gmail:[Gmail]/Trash"))))


(setq gnus-posting-styles
      `((".*"
         (signature ,user-full-name)
         ("GCC" "nnimap+main:Sent"))
        ("nnimap\\+gmail:.*"
         ("GCC" "nnimap+gmail:[Gmail]/Sent Mail")
         ("X-SMTP-Server" "smtp.gmail.com")
         ("X-Message-SMTP-Method"
          "smtp smtp.gmail.com 587 redacted@gmail.com")
         (address "redacted@gmail.com"))))

(setq message-send-mail-function 'message-smtpmail-send-it)
(setq send-mail-function #'smtpmail-send-it)

(setq smtpmail-default-smtp-server "127.0.0.1")
(setq smtpmail-smtp-service 1025)
(setq smtpmail-stream-type 'ssl)


>From what I can tell, this setup isn't working because Gmail uses
port 587, but I've explicitly set it to port 1025 since that's the
port I use for communication with Proton Bridge.

I have a few questions:

1. How would you idiomatically resolve this issue?
2. What’s the correct approach when dealing with multiple accounts
   like this?
3. Is it appropriate to use gnus-posting-styles to override things
   like the SMTP server?
4. Should I use X-SMTP-Server as well as X-Message-SMTP-Method?

I would appreciate any advice or insights you might have on how to
handle this properly.

Thanks in advance for your help!

-- 
Serghei Iakovlev