Error occurred after install web essential 2015

[cberio]

Hello.

1. install Web Essntial 2015
2. restart vs
3. open my solution and open any cshtml files
4. error occur and razor intellisense doesn't work.
5. disable / uninstall doesn't make any change
6. I had to devenv -RestUserData for repair

error msgs are folling..

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.ContainedCodeErrorTaggerProvider1.CreateTagger[T](ITextBuffer textBuffer) at Microsoft.VisualStudio.Text.Tagging.Implementation.TagAggregator1.GatherTaggers(ITextBuffer textBuffer)

[cberio]

i'm using vs2015 enterpise on windows 10.

[madskristensen]

This is not a Web Essentials issue but looks like a Visual Studio MEF corruption issue. Try downloading this extension or follow the instructions to delete the MEF components cache folder https://visualstudiogallery.msdn.microsoft.com/22b94661-70c7-4a93-9ca3-8b6dd45f47cd

[cberio]

thank a lot finally it works! :+1:

[madskristensen]

That's great! Did you install the extension or did you manually delete the component cache folder on disk?