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There should be no ID and password for a wired connection, you just plug your system into the router and it works. However... Your ISP may need some sort of ID and password entered into the router to validate its connection if it is an ADSL one rather than cable. They should have set this up when you had it installed.
Otherwise you could point your browser at the router (I'm assuming you have one as you haven't given any details of your connection)and try address 192.168.0.0 or 192.168.0.1 which should get you the router's login page. Yup! you'd need an ID and password from your ISP to get passed this, you'd be looking for the ADSL set up page once you get access and check the details match those which your ISP supplied. Routers are generally set to DHCP by default and will supply devices plugged in to them an IP normally 192.168.0.<something between 1 and 255> Try setting your network connection to DHCP rather than a static IP.
Does this help?