The ForzaHorizon5.exe file size is roughly in the legitimate version. If your downloaded .exe is much smaller (e.g., 2–5 MB), delete it immediately — it’s fake.
The most common fake file labeled "ForzaHorizon5.exe" is actually a crypto miner. It runs silently in the background, using your GPU to mine Monero. Symptoms: forza horizon 5 exe file best download