The file is not a game itself, but one part of a multi-volume compressed archive. To access the contents, you must have all other parts (e.g., .001 , .002 , etc.) in the same folder and use a tool like 7-Zip to extract them .
: If the extraction fails with a "Checksum error," it usually means one of the parts—possibly .003 —was corrupted during download and needs to be re-downloaded. Grand Theft Auto V.7z.003
If you have .001 but not .002 , extraction will fail halfway through with a cryptic error. Split archives are only as strong as their weakest (or missing) link. The file is not a game itself, but