Unhandled Exception: System.IO.FileLoadException: Could not load file or assembly 'Microsoft.AspNetCore.Hosting

I wanted to put the migration of our web api in IIS and it send me this error message when I set the stdoutLogEnabled to true in the web.config file:

Unhandled Exception: System.IO.FileLoadException: Could not load file or assembly 'Microsoft.AspNetCore.Hosting, Version=2.0.0.0, Culture=neutral, PublicKeyToken=adb9793829ddae60'. The located assembly's manifest definition does not match the assembly reference. (Exception from HRESULT: 0x80131040) at TITSuiteWebapi.Program.Main(String[] args)

But when I wanted to browse in the api, I have this :

Thank you for your help.