Ok. This is a bit of a strange one. I think I've got it terribly wrong and though I'd lay it out there.
A friend purchased a new and very nice iMac. Unfortunately, it will not access the Internet either via cable or wireless. Their router is a very old D-Link and googling reveals that this is an issue. So, I suggest that they get a new router.
Enter on the scene Dynalink RTA1046vw. This will not under any circumstances get a DSL connection. Spent hours - And nothing. I bring it home, plug it in, zap, perfect.
I get them to ring their ISP. They've been told that it's because they have an Adsl2 device but only an Adsl1 connection... Really? Anyone heard of such a thing?
Yes. Happened to a whole bunch of business's here in Palmy in a little shopping center off a smaller exchange in town. They had had their modems for years and then the exchange got upgraded and suddenly no one had internet.