I´m starting to use \"MVC 3\" but I´m facing some little problems. In my Views, when I code something like this:
@if(Request.IsAuthenticated) {
In my case my Packages folder was missing including MVC and Razor so I have updated packages in packages.config, reopened the view and it worked.
Close Visual Studio => Delete the obj and bin folders located in your project => Start Visual Studio
Maybe I am a bit late to answer this question but this easy fix helped me:
Right click the file > Exclude from project. Right click the file > Include in project.
I have solved this issue with the old, good, wise Microsoft default solution: reinstall all the things again.
Uninstall and Reinstall the Visual Studio 2010 and MVC 3 Framework.
For me this just seemed to be the fact that I had compiler warnings. Code would still compile and run ok but it was not until I fixed all the build warnings that my Intellisense starting working.
I had this same issue in MVC 4. None of these solutions worked for me. Instead, in Windows, I went into Control Panel -> Uninstall a program. Select Microsoft ASP.NET MVC 4 in the program list. Click 'Uninstall.' A 'Microsoft ASP.NET MVC 4 Setup' wizard will display. Click 'Repair.'