If part .008 or .010 is missing, the extraction will fail with a "Payload error" or "Unexpected end of data."
The file is not a standalone document or report; it is a specific numbered fragment of a split compressed archive. 5.7z.009
The .009 suffix identifies this as the 9th part of the series. If part
Ensure you have 5.7z.001 , 5.7z.002 ... up to the final number. Use 7-Zip: Right-click the first file ( 5.7z.001 ). Extract: Select "Extract Here" or "Extract to folder." 5.7z.009