i agree with the first statement, however let's entertain this for a second before we uninstall stuff.
do you have a router for your dsl modem? If you do, there might be a firewall or at least a place you need to enable a specific port in your router, check that first then post back. ( I just got a mental picture of you checking for a router and you dont have one, so all you do to check is look down then back up and start typing, NO . . . . well it was funny in my head