I see it has wifi and more so you'll have to work with your IT support about this one. It should work fine on the usual home router with the firewall off but your post is so light on the network details that I can't offer much.
when trying to connect to the internet it will not let me thro the gateway
Looking at the model I don't see why a dongle would be needed. And the router being upstairs doesn't add much detail.
For most HDTVs and devices there are setup instructions so I'll take it for granted that you followed those to the letter. That is, that the setup is without 20 feet of the router or wired for the initial tests.
Is it some USB WiFi stick? If so, this is not going to work.
I have used one of these -> http://www.amazon.com/NETGEAR-WNCE2001-Universal-Internet-Adapter/dp/B007CO5DZ4/
And if I wanted to gamble something like http://www.amazon.com/Wireless-Dreambox-Network-Printer-Microsoft/dp/B005OIB6XI
Folk that are new to networking may fail at using such a thing but that's another story.
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