Because this is a specific file fragment, the "proper content" depends on whether you are looking for a description of what is likely inside or instructions on how to access it. Common Interpretations
: Ensure you have 2019-12.7z.001 , 2019-12.7z.002 , and any subsequent numbers. Use 7-Zip or WinRAR : Right-click the first file ( .001 ). 2019-12.7z.002
: Select "Extract Here" or "Extract to folder." The software will automatically pull data from the .002 part to complete the archive. Because this is a specific file fragment, the