Set up IMAP in my account

Since Sky changed the settings for email to include Yahoo I have been unable to send emails using my own domain name address. As the Sky address works Ok I think it may be it is using IMAP so I would like to include this in my settings but not able to change anything?

you can simply create another account and configure it manually: Go to Tools - Accounts - New account - Mail - Other and click Next.

Hope it helps.