: Sometimes files are downloaded with extra extensions (e.g., .001.zip). Ensure the file ends exactly in .001 for 7-Zip to recognize it as the start of a split archive. How to Extract .7z.001 files - Microsoft Q&A

: Right-click specifically on the file ending in .001 .

: All related part files must be stored in the same folder on your computer. How to Extract the Files

: This error often means you are missing one of the parts or the file was corrupted during download. Double-check that you have the full sequence of files.

: Select 7-Zip from the menu and then click "Extract to [Folder Name]" or "Extract Here" .