Can't Connect To Apartment Provided Internet

I recently moved into a new apartment complex where Internet is included with the rent, meaning that I do not have a personal Internet connection. Instead, the apartment company has a general connection along with a router on each floor of the complex. They then wire out from that connection to an ethernet port in each apartment. Because of that, calling the Internet company doesn't work because they can only tell me that the router on my floor is getting an Internet connection (and unfortunately my apartment is too far away from that router to have signal strength to use it for wireless). Most tenants plug their personal routers into the ethernet ports and use them for wireless connection within their apartments.

When I try to plug my router in, I cannot connect. I get an error message saying that there is no Internet connection. When I plug my Mac directly into the ethernet port, I still get no Internet connection. I've even tried plugging my netbook (PC) in, and get nothing. I have tried network diagnostics, I have used multiple ethernet cables, nothing. The previous tenant apparently plugged her router into the same ethernet jack I am using and had no problems. She has been gone for a few months, and now I cannot connect.