Files with the extension are compressed archives (similar to .zip files). Because they can contain any type of file, they are often used to distribute malicious software.
If you can tell me or what you expected it to contain (e.g., a game mod, a picture set), I can provide more specific safety advice. ME_sisters.7z
this file if it came from an untrusted source, such as an unknown email attachment, a suspicious website, or a peer-to-peer file-sharing network. Files with the extension are compressed archives (similar to