Try to addAdd following in your web.configweb.config file.:
<dependentAssembly> <assemblyIdentity name="System.Net.Http" publicKeyToken="b03f5f7f11d50a3a" culture="neutral" /> <bindingRedirect oldVersion="0.0.0.0-4.1.1.2" newVersion="4.0.0.0" /> </dependentAssembly>