Yes, mIRC has file transfer capability, but it is not a file transfer client. Those would be FTP or some other program specifically written to share files. So you're stealing a movie and seeking help as to why it won't play ? Maybe the quality was so poor it won't work. Maybe it was infected with a virus and it's eating your hard drive information ?

At any rate, Therat is correct, that isn't a mIRC issue. Move along now, nothing to see here.