You will need software capable of handling split 7z archives.
: ZArchiver is a highly-rated mobile option for 7z files. 3. Extract from the First Volume
Do you have all the other ( .001 , .002 , etc.) in that same folder yet?
: You can use built-in tools like Archive Utility or third-party apps like The Unarchiver .
To access the "good content" inside, you cannot open this file by itself. You must follow these steps: 1. Gather All Parts