When setting up your email for Talk Talk Broadband you need to establish it as a POP3 account in your email client, be it Apple Mail, Outlook, Thunderbird or whatever else. The rest of the details are as follows:
Talk Talk Email Settings
E-mail address: username@talktalk.net
Reply-to address: username@talktalk.net
Incoming mail Sever: mail.talktalk.net
Incoming mail account type: POP3
Incoming mail [...]