Sometimes, there are connection problems: maybe somebody was hosting another server and he/she crashed yours.
instead of looking on the list of servers, you can dirrectly use the command
connect IP to connect to a server (where IP = server's ip ; in example:
connect 89.43.194.167).
Note that 89.43.194.167 won't work (that's my ip, and i'm not hosting a server right now).
P.S.: to check your IP, go to
http://www.whatismyip.com .