I'm sorry to hear that you're having this issue.
You might try downloading the newest firmware onto a hard-drive to see if you're able to get your connection working after updating the first time. You can do that at this link, and by clicking the FIRMWARE button by the manuals:
Bought 10 days ago a LED 3D TV model UE40C7000.
I bought also the wi-fi dongle from Samsung and I can connect to my linksys router but I have a big problem: Internet@tv doesn't work at all! I have the 4 green ticks in the network check, I can access my movies on y PC but I can't get internet@tv to work, neither the firmware update to work. After 2 minutes it times out and gets back t regular TV display. I believe this is something related to Samsung servers, because I cant access also the servers to download the new firmware for my TV! Are the servers down for the last 10 days, or is my ISP blocking access to Samsung servers? I am in Portugal and my ISP is CABOVISAO. Any help would be appreciated, as I am thinking in returning the TV and go for the LG Infinia instead...