DDRMenu - Could not locate Razor Host Factory type: System.Web.Mvc.MvcWebRazorHostFactory, System.Web.Mvc

Question

We have tried to upgrade dnn site from v7.3.2 to v8.0.3 but the upgrade was failed and while rolling back the changes the DDRmenu disappeared and the logger shows. The specified dll is present in the bin folder. Can anyone help us?

[ERROR] DotNetNuke.Services.Exceptions.Exceptions - System.NullReferenceException: Object reference not set to an instance of an object. at DotNetNuke.Web.Razor.RazorEngine.Render[T](TextWriter writer, T model) [ERROR] DotNetNuke.Services.Exceptions.Exceptions - System.InvalidOperationException: Could not locate Razor Host Factory type: System.Web.Mvc.MvcWebRazorHostFactory, System.Web.Mvc at System.Web.WebPages.Razor.WebRazorHostFactory.CreateFactory(String typeName) at System.Collections.Concurrent.ConcurrentDictionary2.GetOrAdd(TKey key, Func2 valueFactory) at System.Web.WebPages.Razor.WebRazorHostFactory.CreateHostFromConfigCore(RazorWebSectionGroup config, String virtualPath, String physicalPath) at System.Web.WebPages.Razor.WebRazorHostFactory.CreateHostFromConfig(String virtualPath, String physicalPath)

Answer 1

How did you roll back? You should have reverted to the old version of the database and the old files. Did you delete all of the files before restoring?