XDCC-Catcher is a client that uses a fake mIRC version reply to evade bans that are set against it on many channels and on many networks. Despite some people's efforts to inform the author's of the client that this is abusive behaviour, they think it is their right to evade things.
mIRC is not a file trading client, XDCC bots 99% of the time provide illegal files. IRC is not the place to get files anyway, it was never designed for such a purpose.
XDCC-Catcher is not affiliated with mIRC in any way.