Razor intellisense not working in VS 2015

Question

When I load up my VS2013 projects in 2015, all my razor views are filled with red squiggly underlines.

@model, @Scripts @url, @Html.Partial, lambda expressions

Intellisense is now fairly useless as it seems to be missing half the options.

Solutions I've seen involved deleting .vs folder, and devenv.exe /ResetUserData, however these don't work for me.

I'm on a fresh install of VS 2015 Community using the same install files as my colleagues. None of them have the razor issues, and they're working on the same projects as I am.

Any idea how to fix this?

Edit...Further Info! I uninstalled/reinstalled VS 2015 Community, opened my projects, and the razor worked! I then clicked on a notification saying to update NuGet. NuGet update installed, VS restarted, razor stopped working again. So the NuGet update is breaking razor??

Every time I open a razor file it says "An exception has been encountered. This may be caused by an extension. You can get more information by examining the file 'C:\Users\Jonathan\AppData\Roaming\Microsoft\VisualStudio\14.0\ActivityLog.xml'. "

In the activity log I get the following error

"System.Reflection.TargetInvocationException: Exception has been thrown by the target of an invocation. ---> System.ArgumentException: Item has already been added. Key in dictionary: 'RazorSupportedRuntimeVersion' Key being added: 'RazorSupportedRuntimeVersion' at System.Collections.Hashtable.Insert(Object key, Object nvalue, Boolean add) at System.Collections.Hashtable.Add(Object key, Object value) at System.Collections.Specialized.HybridDictionary.Add(Object key, Object value) at Microsoft.VisualStudio.Utilities.PropertyCollection.AddProperty(Object key, Object property) at Microsoft.VisualStudio.Html.Package.Razor.RazorVersionDetector.Microsoft.Html.Editor.ContainedLanguage.Razor.Def.IRazorVersionDetector.GetVersion(ITextBuffer textBuffer) at Microsoft.Html.Editor.ContainedLanguage.Razor.RazorUtility.TryGetRazorVersion(ITextBuffer textBuffer, Version& razorVersion) at Microsoft.Html.Editor.ContainedLanguage.Razor.RazorErrorTagger..ctor(ITextBuffer textBuffer) --- End of inner exception stack trace --- at System.RuntimeMethodHandle.InvokeMethod(Object target, Object[] arguments, Signature sig, Boolean constructor) at System.Reflection.RuntimeConstructorInfo.Invoke(BindingFlags invokeAttr, Binder binder, Object[] parameters, CultureInfo culture) at System.RuntimeType.CreateInstanceImpl(BindingFlags bindingAttr, Binder binder, Object[] args, CultureInfo culture, Object[] activationAttributes, StackCrawlMark& stackMark) at System.Activator.CreateInstance(Type type, BindingFlags bindingAttr, Binder binder, Object[] args, CultureInfo culture, Object[] activationAttributes) at System.Activator.CreateInstance(Type type, Object[] args) at Microsoft.Html.Editor.ContainedLanguage.Common.ContainedCodeErrorTaggerProvider`1.CreateTagger[T](ITextBuffer textBuffer) at Microsoft.VisualStudio.Text.Tagging.Implementation.TagAggregator`1.GatherTaggers(ITextBuffer textBuffer)"

How do I fix this?

Answer 1

This could fix similar problems (I got it from somewhere, unfortunately I cannot remember, on Github)

• Close VS Studio
• Run command prompt as Administrator
• In command prompt:

  > cd "%ProgramFiles(x86)%\Microsoft Visual Studio 14.0\Common7\IDE"
  > devenv /updateconfiguration
  > devenv /clearcache
  

  I hope the above will be helpful to someone.

Answer 2

None of these solutions fixed it for me. What worked was ensuring my webpages version was up to date. So

<add key="webpages:Version" value="3.0.0.0" />

in the web.config, instead of version 2.0.0.0

And then closing and reopening visual studio with the same solution.