I tried to open port 465, But…
ufw allow 465/tcp ufw allow out 465/tcp
sudo nmap -sS -p 20-2550 localhost Nmap scan report for localhost (127.0.0.1) Host is up (0.000019s latency). Not shown: 2528 closed ports PORT STATE SERVICE 22/tcp open ssh 80/tcp open http 443/tcp open https
telnet -4 smtp.gmail.com 465 telnet: Unable to connect to remote host: Connection timed out
Unable to open port 465
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