1. Set the application address pool to unmanaged code
1. Tip: About the "HTTP 500.19" error when running ASP.NET Core site on IIS
Install dotnet-hosting-3.1.2-win.exe
ASP.NET Core 3.1 Runtime (v3.1.2) download address:
二、HTTP Error 500.30 - ASP.NET Core app failed to start
Change hostingModel in web.config to: outofProcess