Я столкнулся с проблемой несовпадения версий в моем проекте MVC.
Error CS1705 Assembly 'System.Web.Http.Cors' with identity
'System.Web.Http.Cors, Version=5.2.7.0, Culture=neutral,
PublicKeyToken=31bf3856ad364e35' uses 'System.Web.Http, Version=5.2.7.0,
Culture=neutral, PublicKeyToken=31bf3856ad364e35'
which has a higher version than referenced assembly 'System.Web.Http'
with identity 'System.Web.Http, Version=5.2.3.0, Culture=neutral,
PublicKeyToken=31bf3856ad364e35'