That message occurs when you try and message someone, or a channel, or sometimes when you /whois someone and they simply do not exist (or the user is not connected at that time). It's like talking to someone through the telephone, then they put the phone down and you still trying to talk to them. Although they still exist, the phone isn't connected to theirs and so you can't talk with each other.
or do I have to type something in the mirc chat window in order to get a file??
Be aware that mIRC is not a file trading program like other 'peer 2 peer' programs out there. It's a chat program, so sorry if you've been told or heard otherwise and thought you could get mp3s/movies/whatever from IRC. We do not help with that as it's illegal if that's what you were intending.
If you're attempting a DCC Send/Get connection from someone make sure you're typing their nickname
exactly. If you were sending me a picture you must use
/dcc send mentality NOT
/dcc send Ment or another variation of my nickname.
Regards,