Cannot resolve symbols Html, Url

ReSharper keeps saying it cannot resolve symbols 'Url' and 'Html' for all my view pages.  I tried doing a Clean Solution, Rebuild Solution, and Resharper --> Options --> Clear Caches and none of that helped.  The only thing that fixes it is deleting the entire _ReSharper.ProjectName folder.  However that means it has to reanalyze the whole solution again and this only fixes the problem temporarily - the problem returns again at some point later on.

It is as if Resharper stops realizing it is an ASP.NET mvc project or something at some point, it suggests System.Policy.Url for <%= Url.Content(...