It could be many things...some may say it depends on the network you are trying to connect to others may ask if you have a router to give the information so you can be helped....all have to say is if the networks you are trying are:
DALnet or Chatnet
Good luck with that. DALnet has recently been attacked and certain servers are up an running you can view a list of active Dalnet servers here
. If it is Chatnet you are trying to connect to then you should be patient. To the best of my knowledge, Chatnet has recently been under some kind of attack just weeks after K9's return and there was at least 4 servers working. Last night no servers were available that I know of. Chatnets chatters are encouraged to be patient while they resolve the situation.
You can also use the Search feature
just seach for
"connection timed out" or "connection" or "timed out" in the search field and make sure you have "All forums" and "All posts"
I hope this is helpful in anyway.