Are you sure that is a "real" power source at this point? Have you pulled it from the wall to make sure it is actually wired up? It could be a secret hiding spot meant to look like an outlet, where a previous tenant stashed some bills or jewelry. Some people are clever.
You should be fine if it is actually dead, just be careful where you put your fingers, since maybe a wire is loose or broken inside the outlet receptacle itself. If it is really wired up and the connections are snug, what people are trying to tell you is that it could be wired in with a GFCI outlet that is somewhere else in your house, and that GFCI outlet itself is tripped, and therefor your power downstream from that GFCI (hypothetically, this outlet) is also dead. The GFCI has to be reset at the GFCI outlet itself, not the breaker panel.
Conversely, since you are renting, put the landlord onto fixing this issue, if it looks like it is wired up but you still can't find out why it's not hot.