There's no need to post the same question on multiple forums. And this isn't real-time chat, it could be hours before someone gives you a satisfactory answer, be patient.
For all this talk of DCC you don't seem to be mention chatting. You are aware that mIRC is primarily a
chat client aren't you? With that in mind downloading 400mb files using DCC is slow, inefficient, and if I remember correctly can lead to very heavy fragmentation of your hard drive.
As for your question I don't know the answer. Have you tried using the forum's
Search feature?
