Hi again, arewtee.
Hell, man; don't go getting the impression that I'm an 'expert', 'cos I'm not..!
I'm perhaps what you might call 'handy' with my OS of choice, which these days is Puppy Linux.....but when it came to Windows (XP or otherwise), I was pretty much as lost as anybody else!
'Murky and mysterious'. No, you're not wrong. Networking is a 'murky' business.....to me, at least. I understand the basics of it, but like most people, I don't understand why it is that the system makes some of the choices that it does. In Linux, at least, you get to see what the choices are (and you do at least get told why).....but Windows has always hidden the mechanics of setting up your internet connection. I believe Microsoft think that most people just don't want to know what's going on; heaven above knows, they could just be right!
I do know that Win 7 boxes are a total PITA to set up to make them 'talk' to XP boxes.....but I don't think this has any bearing on your problem. It's been so long since since I used a modem that I've honestly forgotten the tricks I had to employ, in order to make them function properly.
And as for the eyes glazing over, and thinking 'Ooh, my brain is starting to hurt..!', I think it's a common symptom of using Windows! For me, at least, I enjoy using Linux, and take great pleasure in 'messing about' with things to make them do what I want them to.....and it's worthwhile, because everything is solvable in Linux, sooner or later.
Anyway, back on track:-
You sound as though you have something very similar to my own setup. I also have what's called an 'Internet Gateway', but mine, too, is permanently disconnected. My internet connection also takes place via the 'Local Connection' (to put it in terms that you'll understand). I believe the 'Gateway' to be used if you use one machine in a network to access the internet, and then the other machines in that network, in their turn, access the 'net via that 'gateway' box. It's not a common way of doing things for your average home user, however; I think it's for large numbers of machines, perhaps in a commercial or office environment, for instance, where the system administrator needs to able to closely monitor network traffic.
So I don't think that's got anything to do with the problem.
I think it all boils down to your modem (router?) settings. Which I'm not an 'expert' with! Like most folks, I tend to use the default settings, unless I need to alter something for network 'sharing'.....and that's rare.
Sorry I can't help any further. Windows is not my day-to-day OS, but your post just happened to catch my eye. I sincerely apologise if you feel I'm wasting your time.....and to the staff, too.
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