Click on Email
Click on Skip this and use my existing email
Your Name: Your full name
Email Address: The email address you are trying to access
Password: The password for the email address
Then click on Continue
Click on Manual config
Changes the following values:
Server hostname (incoming and outgoing): mail.yourdomainname.com (replace yourdomainname.com with your domain name)
Port: 143 for incoming and 25 for outgoing (some ISP’s require this to be 587)
SSL: Both incoming and outgoing to None
Authentication: Both to Autodetect
User Name: This should be your email address
Outgoing: This should be your email address
If you get this screen, then click I understand the risks and then Done
Please note: This is for Thunderbird version 31.1.1 other versions may be slightly different.