If youre using the current mIRC version 6.1, type Alt+O to open the options menu list, go to DCC item and either double click it or click the + to open the sub-menu tree under DCC, and select the Ignore item. In here you find a Method option box with choices for "Disabled" which turns this option off, or "ignore only" which means your mirc will ignore only the file types listed below, or "accept only" which means your mirc will only accept the file types listed below and ignore all others. You can add to the file types accepted or ignored listing by typing in a file type *.xyz and clicking Add. If youre still using an older mIRC ver, these options were found in the DCC/Folders option list.
