If the file was part of a larger set (e.g., R0721.7z.001 , R0721.7z.002 ), ensure all parts are in the same folder. You must open the .001 file to begin extraction.
Sometimes files are incorrectly named. If the file has a double extension (like R0721.7z.7z ), try renaming it to just .7z . R0721.7z
While "R0721" is a generic naming convention, it is often seen in: If the file was part of a larger set (e
when trying to open this file, or do you need help identifying its original source? ⌛⌛ Text search inside a 7z file R0721.7z
Use the p7zip package. You can extract it using the command: 7z x R0721.7z . Common Troubleshooting Tips