A file ending in .004 cannot be opened on its own. You must download every preceding part (e.g., .001 , .002 , and .003 ) and ensure they are all saved in the on your computer. If even one part is missing or renamed differently from the rest, the extraction will fail. 2. Use the Right Software

A popular alternative that can handle .7z extraction and conversion.

The original open-source utility designed for this format. It is widely considered the most reliable for joining split parts.

Here is how to successfully handle and open these multi-volume files.

The software will automatically detect parts .002 , .003 , and .004 , combining them into the original video file.

While Windows 11 now has built-in support for standard .7z files, it often struggles with multi-volume split archives like this one. For the best results, use a dedicated tool: