Just found this on tesco so have answered my own question! E-mail status Below is a description of the service status of the E-mail service.
Serious fault or a service is down.
Title Date/Time Details E Mail and Webmail 01/08/11 @ 12:16 Tesco Internet customers may be experiencing intermittent problems accessing their E Mail. Please accept our apologies and retry accessing later, as the fault causing these issues is currently under investigation. Customers may also be seeing a delay in receiving some mails sent since Monday 01/08. Tesco Internet apologises for any inconvenience caused.