The file extension signifies that you are looking at the first part of a split compressed archive . This format is typically used when a very large file or folder is broken down into smaller, more manageable pieces for easier sharing or storage. What is a .7z.001 File?

: If even one part of the sequence is missing (e.g., you have .001 and .003 but not .002 ), the extraction will fail with an error.

7zip file with numbers on it like 001 means that you only have a part file of the whole compressed file. Microsoft Learn Does 7z compress better than zip? - Microsoft Community Hub