Thunderbird v.1.5

1. Open Thunderbird,
2. Select 'Account Settings...' from the 'Tools' menu.

3. Click 'Outgoing Server (SMTP)' on the left.
4. 'Outgoing Server (SMTP) Settings' window appears on the right
5. In the field 'Server Name:' enter: smtp-server.com,
6. Type port number: 25 or any available port number
7. Check 'Use name and password', then enter 'SMTP User Name'
8. Select 'TLS' under 'Use secure connection', and click [OK].