I have changed the network password for my wireless network connection. After changing the password all my roommates are able to connect to the wireless network with new password.
One of my friends is not able to connect to it, and her system waits for the network to detect for a long time. It's an Windows XP system. I am also using an XP system, but I am able to connect. We used trial and error to troubleshoot the system.
Note: She is able to connect to the other flat's wireless network, but not ours.