You've connected to the wrong server then, although I don't know why mIRC should disappear.
Anyways, you need to get on to server : irc.what.cd
The one you connected to is probably : irc.rizon.net
Reading the guide, you should find out where you can replace one for the other. If not, you can just log on to whatever server and then write in the text box "/server irc.what.cd" and your client will connect to it.
