Configure & Secure Email - Mozilla Thunderbird V2.0+
- "Tools > Account Settings"
- Select "Server Settings" under the appropriate account that you want to modify.
- Check "Use secure connection (SSL)". This should change the port to "993" for IMAP, and "995" for pop.

- Go to "Outgoing Server (SMTP)."
- Select email account > select Edit button.
- In SMTP Server dialog box, under Security and Authentication, check "Use name and password" and enter your username.
- Under "Use secure connection," check "SSL" and change the port to "465".
(*) If you use an SMTP server other than your
default SMTP server, you should change the SMTP settings (5-6 above) by going to
"Advanced" SMTP settings and editing the settings for the appropriate server.