Without knowing which network you are trying to connect to, or the website address, how are we supposed to help you. If it is EFnet see my post a few posts up, if it is realmworld then see This post
If it is the latter then I can only surmise, the website is moving or has closed down.
Please remember this is a mIRC forum. We have no real knowledge of individual networks/servers or websites or the status of channels.
Good luck to you all in this matter

Happy mIRC user on Linux