A few recent entries to the list of problems with TalkTalk seem like they could be software related. People not being able to use MSN Messenger or having problems getting their TalkTalk email for instance. The first one could be caused by a badly configured firewall which the TalkTalk software installs and the second by an apparent typo in the default mail settings.
The reason I bring this up is because installing the the TalkTalk software is one thing I never did. Since I was going to use a router with a modem built in I didn’t bother waiting for my welcome pack and just tried from the day they said the broadband would be active and everything worked fine. The irony is one of the first things any broadband technical support would ask you if you had a problem would be whether you are using a modem or a router since a modem should be simpler.