This is a common error message, please check out
this thread for information. You could also use the Search feature (located at the top) - expand to 'All Forums' and 'All Posts' for best results.
Do heed the warning in that thread - mIRC isn't for mass file trading, and there are dangers when doing so, if that's what you're doing. Files such as mp3s, movies, etc. are also illegal.
Regards,
