Given the context, I'm going to assume you're asking for a report on how to fix or troubleshoot issues related to Forza Horizon 4, possibly involving a generic repair approach for errors encountered on the Steam platform.
Overlays from Discord, NVIDIA GeForce Experience, or MSI Afterburner cause FH4 to crash on launch. Disable them globally. fh4fixrepairsteamv2genericrar
Because these files are distributed via unofficial sites and file-sharing mirrors, they are prime targets for trojans or password-stealing malware. Given the context, I'm going to assume you're