"Napoleon.Total.War.part4.rar" is the fourth segment of a multi-part RAR archive required for installing large mods like Napoleonic Total War III, and it cannot be used individually. To extract, all parts must be in the same folder, and the extraction process must be initiated from the first file ( part1.rar ) using tools like WinRAR or 7-Zip. For a guide on extracting multi-part files, see Newshosting Support .