I have a cable connection via Paradise and TelstraClear. My speed is 256K and I'm very happy with the connection from my machine. My kids have PCs connected to mine using TCP/IP and share my internet connection using ICS. They both run XP Home and I'm using Windows 2000 Professional.

My problem is that when I first installed the OS on my machine, their connection to the Internet was as fast as mine. At some point, something I do causes their connection to slow down to the point where some sites are unuseable because of timeouts. Several times I've reloaded the OS and attempted to find what process it is that causes the problem but so far with no success. It seems to run OK for a while and then I get the message that it's gone slow again. I've tried shutting down all the things like the firewall (Zone Alarm Pro), virus checker and all the other TSRs I have on my machine but it doesn't appear to be them.

My latest suspicion is that it may be connected with running a program that was supposed to set my various settings to optimise my Internet connection. Perhaps that's set something that screws up the ICS? Rather than reload the OS again, would anyone know anything I could try that may affect the speed of the connected machines? It doesn't seem to affect the ordinary network connection to my machine which is why I think it may be something to do with my Internet settings.