Email apps ask for a port and a security type. Getting the pair right is the difference between connecting instantly and a mysterious timeout.
The ports for Traxio mail
| Service | Port | Security |
|---|---|---|
| IMAP | 993 | SSL/TLS |
| POP3 | 995 | SSL/TLS |
| SMTP | 465 | SSL/TLS |
| SMTP | 587 | STARTTLS |
SSL/TLS vs STARTTLS
- SSL/TLS (sometimes “implicit TLS”): the connection is encrypted from the first byte. Used on 993, 995 and 465.
- STARTTLS: the connection starts plain, then both sides agree to switch to encryption before anything sensitive is sent. Used on 587.
Both end up encrypted. “SSL” is the older name; modern connections use TLS either way.
Mismatches
| Setting | Result |
|---|---|
| Port 465 with STARTTLS | Hangs, then times out |
| Port 587 with SSL/TLS | “Wrong version number” or handshake error |
| Port 993 with no encryption | Connection refused or garbled |
Unencrypted ports
Ports 143 (IMAP), 110 (POP3) and 25/26 (SMTP) can work without encryption, which sends your password in readable form. Don’t use them.
Networks that block ports
Some hotel, school and workplace networks block mail ports. If email works on mobile data but not a particular Wi-Fi network, that network is the cause.