Well, that was embarrassing. I’ve just figured out why my machine was the only one that could (a) get DHCP information from my wireless router and (b) connect to the Internet through it. That in itself is a good thing. The fact that the problem turned out to have been caused by my stupidly misunderstanding what one of the settings on the router did is rather less good.

Still, you live and learn I suppose. Probably good to be reminded from time to time how much there is that I don’t know when it comes to these computer thingies.