GTi - I use a standalone modem/router all-in-one thingy and my PC's connect via ethernet cable to it.... I've not had a prob with it before, like this anyway (has randomly dropped ehternet ports before now, but when it does that, the internet still works, but the PC's show up as not connected to the router) and not had to re-enter username and password....

I think this must have been a DNS problem or something with Orange...

What was odd tho was that my router had the ADSL light lit up the whole time - but the data light wasn't flashing as normal.....