Get a Dlink DI 5XX wireless router to work with Ntecomm NB5 dsl modem

I have a netcomm nb5 dsl modem which when connect directly can acces promptly applications/pages such as myspace, messenger even register online with McAfee but when i connect my dlink di5XX w/less router and connect (via ethernet) i can’t acces those application.
what change do I need to make on either the modem or the router in order to be able to run/access the net without any fuss?
Your help will be much appreciated.
Thanks