princessamy86 it seems the school has blocked port 6346 which LW uses by default, else, something on your computer is blocking that port. Which sounds like a firewall. (The school may have recently changed their policy on bandwidth use. I'm sure they can detect gnutella & other p2p network programs running on the school's network.)

Go to LW's menu bar, Tools>Options>Advanced & change the listening port from 6346 to another. Also, I doubt UPnP will work I don't know. Try setting it to manual port forward. And also change the port no.
Try these ports: 1111, 80, 3500, 4008, 1203, 10000, 15189, 20282, 22817, 443, 427, 34599, 40475, 64049, 20-22. You should probably use the same port no. for both listening port & manual PF port.

You'll need to press the apply button after the change. I'm not sure whether you need to relaunch or not. But go to File menu > Disconnect. Wait a min, then File>Connect. Give each port you try at least 15+ mins to try to connect.