Mozilla Setup
Step 3

Step 3:
After saving the information about the new Outgoing Server, select your new Email Account from the list.  In the Outgoing Server (SMTP) field, select the SMTP Server from the drop-down list.  Other items on the page were automatically created when you entered the account details - alter and extend as necessary.

Click on the Server Settings option under your new account.  Make sure the entries in the following fields correspond to the settings given here:
Server Name: rsj24.rhostjh.com
Port: 995
Username: Your Full Email Address
Security Connection: SSL or SSL/TLS
Use Secure Authentication: Yes
As shown on the right.

After saving these changes you should be able to send and receive emails.  Other aspects of Account Configuration are optional and self-explanatory.

See Also
Account Setup Chapter in the Thunderbird FLOSS Manual for more details.

Setup Other Devices