Mutt stopped sending email

I'm using mutt to send mail like this:

mutt -s "Subject" email@gmail.com <<< "Text"

A few days ago, mutt stopped working and now I am getting this error:

msmtp: cannot read from TLS connection: the operation timed out
msmtp: could not send mail (account default from ~/.msmtprc)
Error sending message, child exited 74 (I/O error.)

• version: Mutt 1.9.4

• /.muttrc:

set sendmail="/usr/bin/msmtp"
set use_from=yes
set from=my.email@gmail.com

• /.msmtprc:

defaults
logfile ~/msmtp.log
account gmail
auth on
host smtp.gmail.com
from my.email@gmail.com
auth on
tls on
tls_trust_file /etc/ssl/certs/ca-certificates.crt
user my.email@gmail.com
password "mypassword"
port 587
account default : gmail

What I've done:

I created an application specific password for Mutt on Google with 2FA but am still getting the same error.

The output of telnet and ping command shows a successful connection to the SMTP server of Gmail (smtp.gmail.com) on port 587.

Switch to port 465 and getting: msmtp: the server sent an empty reply with code 76 (Remote protocol error.)

Both port 587 and 465 works fine with swaks -tls, email successful delivered.

I had this problem recently too (my existing config just stopped working one day in March 2023). I found this page to get me going, in particular:

set from = "your_email_address"
set realname = "Your Name"

# Gmail
set imap_user = "your_email_address"
set smtp_url = "smtps://YOUR_EMAIL@smtp.gmail.com:465/"
set smtp_authenticators = 'gssapi:login'
set imap_pass = "your_app_specific_password"
set smtp_pass = "your_app_specific_password"

# Ensure TLS is enforced
set ssl_starttls = yes
set ssl_force_tls = yes

It seems to me that it was the TLS stanza that fixed my issue. HTH you!

• You might not be able to connect to port 587 on that host ( rate limits ? ) , ask your ISP if this problem persists
• If port 465 is open from your side you may use the proper ssl settings

  # Use TLS on port 465
  port 465
  tls on
  tls_starttls off