As I said on another thread recently .............
Don't bother with their helpdesk telephone customer services - a waste of time.
Go to their members forums -- http://www.talktalkmembers.com/forums/
it's monitored by their UK support staff.
Read the bit highlighted in red (to send them your phone and account number), then once you're registered - if you have a problem, just post in the support forums. But also read the sticky's at the top of the broadband support section and include that information in any query you raise - saves a lot of time, and far more productive than BT's usual help - is your pc switched, have you tried rebooting the router etc. etc..