Type ‘Object’ is defined in an assembly that is not referenced (NET Standard 2.0/.NET Framework 4.6.1) [duplicate]
Try to add a reference to netstandard in web.config as below: <system.web> <compilation debug=”true” targetFramework=”4.7.1″> <assemblies> <add assembly=”netstandard, Version=2.0.0.0, Culture=neutral, PublicKeyToken=cc7b13ffcd2ddd51″/> </assemblies> </compilation> </system.web>