Why does "Version 3" matter? Autodesk actively fights against keygens. The original X-Force keygen for 2018 was detected and blocked by Autodesk’s genuine service checks. However, Xf-adsk2018-x64v3.exe incorporated improvements:
Running software designed for an older version of Windows or an older Autodesk product on a newer system might require compatibility modes or updates. Xf-adsk2018-x64v3.exe
If you did not intentionally download this file but suspect it is present (perhaps from a previous user or a compromised installer), look for these indicators: Why does "Version 3" matter
Regularly back up your system to prevent data loss. Xf-adsk2018-x64v3.exe