You may have the box checked that shouldn't be
Setup instructions can be found here
To double check your settings,
Open Outlook Express
click on tools
click on accounts
click on the email account
click on properties
under servers the log in using secure password authentication should be unchecked.
Recently, when trying to receive or send messages the following error is displayed.
The server responded with an error. Account: 'pop3', Server: 'pop3.blueyonder.co.uk', Protocol: POP3, Server Response: '-ERR Can not connect to e-mail server. Error:100502 ', Port: 110, Secure(SSL): No, Server Error: 0x800CCC90, Error Number: 0x800CCC90
I would be grateful for any advice.