Failed to connect to server

I have had this problem for a while now. I'm trying to connect to server 84.250.17.82, but after 5 seconds client says "Failed to connect to server". Other people can connect to server just fine. I can also connect to other servers just fine. I have also been able to connect this server before just fine. (I think that was last spring.) Server name and password are right, this has been checked so many times already. I have also tried to ping server with cmd, it says

Pinging 84.250.17.82 with 32 bytes of data:
Reply from 84.250.31.73: Destination host unreachable.
Reply from 84.250.31.73: Destination host unreachable.
Reply from 84.250.31.73: Destination host unreachable.
Reply from 84.250.31.73: Destination host unreachable.

Ping statistics for 84.250.17.82:
Packets: Sent = 4, Received = 4, Lost = 0 (0% loss),

Failed to connect to server