WebAPI found reference error when I have the assembly

I did:

get-project <project_name> | uninstall-Package Microsoft.AspNet.WebApi.WebHost -force

Then reinstalled (with specific version consistent with those in other projects)

get-project <project_name> | install-Package Microsoft.AspNet.WebApi.WebHost -Version 5.2.2

This solved the problem for me.

A forced reinstall of WebAPI could do the job:

 update-package microsoft.aspnet.webapi -reinstall

I uninstall some nuget packages in my project, including the MVC, and install all over again. Resolved. Thanks everybody for help me.

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