Please confirm you have internet access by opening your web browser on the device you wish to use for email. If you're accessing this documentation on that machine, you have already performed this step.
Open Thunderbird. Open Options and Account Settings from the menu shown.
Choose the option to Add Mail Account, as shown.
Enter your account data, then choose Continue.
Thunderbird will not have the new CICI servers on file and won't guess what they are correctly. Choose Manual Config to enter the proper settings.
Enter all server information in the new boxes exactly as shown. Your display name, password, and email address will not be changed from the previous screen. Please enter your full email address for the two Username boxes. Select (Re-)Test to verify the settings. Click done when they are accepted.