: If the extracted content contains an .exe , .bat , or .msi file and you aren't 100% sure of the source, do not run it .

: You cannot open part4 on its own. You must have all preceding parts (part1, part2, part3) and any subsequent parts in the same folder.

Do you have the of this archive downloaded to the same folder yet? Gunsmith Part 4 - RELEASE 1.0 Guide | Escape From Tarkov