On the account setup window, click Manual config. and use the settings given here:

https://reagancom.zendesk.com/hc/en-us/articles/30010048230931-General-Email-Client-IMAP-Settings

sfhowes, Thank you for your response, however, i did try that previously without success. Thunderbird failed to find the settings for the email account.

If TB 'fails to find' the settings, it just means they aren't in the ISP database that applies to common providers. Try this: click the icon at the left end of the status bar to go Offline, then add the account with the recommended settings. After the account is added, click the icon to go back online and see if TB connects to the mail server.