If you aren't 100% sure about the source, upload the file to VirusTotal . It will scan the archive against 70+ antivirus engines to ensure it's not a "Trojan" disguised as a project file.
That specific file name, , doesn't appear in public databases or common software repositories. Based on the naming convention (a likely "LoOnly" project prefix and version "008"), it is almost certainly a custom archive, a private mod, or a specific dataset. Since I can't "see" inside your local file, 7z archive: 1. Identify the Source Before opening it, try to recall where it came from: LoOnly_Po-008.7z
Because .7z files can contain executable scripts or malware, use a "sandboxed" approach: Use 7-Zip or WinRAR. If you aren't 100% sure about the source,
It’s a mod or configuration data for a specific engine. .csv , .sql , .xlsx : It’s a data export or database dump. Based on the naming convention (a likely "LoOnly"