Standard Windows or Mac compression tools often fail with multipart archives. You should use specialized tools like 7-Zip for Windows or The Unarchiver for Mac. 2. How to Open SC2.7z.001 (Step-by-Step) For Windows Users (Using 7-Zip) How to Open and Extract .001 Files - Newsgroup Reviews
Every part must have the exact same base name. SC2.7z.001
You must have every numbered file in the series (e.g., SC2.7z.001 , SC2.7z.002 , up to the final number). Standard Windows or Mac compression tools often fail