1. In the left pane right click on the Email account you are having issues with (ex: yourusername@gtconline.com), and then click on Settings.

  2. In the Account Settings window make sure the account name is yourusername@gtconline.com, then click on Server Settings on the left.

  3. In the server settings window make sure the settings are as follows:

    imap.gtconline.com Port 143
    Username: yourusername@gtconline.com
    Connection Security: STARTTLS
    Authentication Method: Normal password

  4. Next Click on Outgoing Server (SMTP), then click on the Edit… button.

  5. Ensure your SMTP Server settings are as follows:

    Server Name: smtp.gtconline.com
    Port: 587
    Connection Security: STARTTLS
    Authentication Method: Normal password
    User Name: yourusername@gtconline.com