I get this same problem can be OK for days then do it several times in same day, been troublesome this week so will try to get to grips with it this week comming when I have more time to mess with it.

Won't connect in any browser IE8 FF or chrome(running XP connected by E - cable to netgear asdl router)

running diagnose in IE, Clearing cache, flushing dns, none seem to work always have to power down / up netgear router before it will reconnect.

Was thinking of trying to borrow another router -

I'll keep my eye on this thread and hope a network wizard can give us an answer.

Are you connected by cable or wireless to the router?

Do other devices connect via the router when the problem occurs on your PC?

May be we can pin it down to a PC or router problem.

I too have been having a similar problem, but it's only the ethernet connection that is lost - wireless continues to work, so my problem must be the router. I would change it but we are supposed to be getting Infinity soon, so doesn't seem much point in buying a new router when one will be provided.