Because the servers are very busy with a lot of people like yourself who have been told that their account will be closed on 15th February 2009. Try very early in the morning or use POP.
POP3. The following settings apply:
Incoming mail server address (POP3): pop3.lycos.co.uk
Username/login: “Your complete e-mail address”
Password: “Your Lycos Mail password”
Do not use SSL Connection.
If required outgoing mail server address (SMTP): smtp.lycos.co.uk