Open the Mail app:

Select Add account…

Select ADD NEW ACCOUNT

Enter Email Address and Password and select MANUAL SETUP :

Select IMAP account

Enter Email address, Username (same as Email address), Password

Enter mail.interdns.co.uk as the INCOMING SERVER, IMAP server setting

Select TLS as the Security type

Enter 143 as the Port

Enter smpt.interdns.co.uk as the OUTGOING SERVER server setting

Select TLS as the Security type

Enter 25 as the Port

Turn ON, Authentication required before sending emails

Re-enter Username and Password and

Select SIGN IN