title: Error starting Visual Studio 2012
body: <p>I'm getting an error message every time I start Visual Studio. Since I'm also seeing some unexplained behavior in my project, I'd like to resolve this issue.</p>
  
  <p><strong>Error Message</strong></p>
  
  <blockquote>
    <p>An exception has been encountered. This may be caused by an extension.</p>
    
    <p>You can get more information by examining the file 'C:\Users\Jonathan\AppData\Roaming\Microsoft\VisualStudio\11.0\ActivityLog.xml'.</p>
  </blockquote>
  
  <p>When I look at the log file, I find two exceptions:</p>
  
  <p><strong>Error 1</strong></p>
  
  <pre><code>Exception Type       : System.Windows.Markup.XamlParseException
  Exception Message    : Provide value on 'System.Windows.StaticResourceExtension' threw an exception.
  Exception Stack Trace:
      at System.Windows.Markup.WpfXamlLoader.Load(XamlReader xamlReader, IXamlObjectWriterFactory writerFactory, Boolean skipJournaledProperties, Object rootObject, XamlObjectWriterSettings settings, Uri baseUri)
      at System.Windows.Markup.WpfXamlLoader.LoadBaml(XamlReader xamlReader, Boolean skipJournaledProperties, Object rootObject, XamlAccessLevel accessLevel, Uri baseUri)
      at System.Windows.Markup.XamlReader.LoadBaml(Stream stream, ParserContext parserContext, Object parent, Boolean closeStream)
      at System.Windows.Application.LoadComponent(Object component, Uri resourceLocator)
      at SquaredInfinity.VSCommands.UI.Views.DefaultAlertView.InitializeComponent()
      at SquaredInfinity.VSCommands.Foundation.Services.VSCUIService.GetDefaultAlertViewModel(String alertMessage, String alertDialogTitle)
      at SquaredInfinity.Foundation.Presentation.Services.UIService.GetDefaultAlertViewModel(String alertMessage)
      at SquaredInfinity.Foundation.Presentation.Services.UIService.ShowAlert(String message)
      at SquaredInfinity.VSCommands.VSCommandsPackage.Initialize()
  Exception Data   : [EmptyOrNull]
  Inner Exception:
  Exception Type       : System.Exception
  Exception Message    : Cannot find resource named 'VSC.Button'. Resource names are case sensitive.
  Exception Stack Trace:    at System.Windows.StaticResourceExtension.ProvideValueInternal(IServiceProvider serviceProvider, Boolean allowDeferredReference)
                        at System.Windows.StaticResourceExtension.ProvideValue(IServiceProvider serviceProvider)
                        at MS.Internal.Xaml.Runtime.ClrObjectRuntime.CallProvideValue(MarkupExtension me, IServiceProvider serviceProvider)
  Exception Data   : [EmptyOrNull]
  </code></pre>
  
  <p><strong>Error 2</strong></p>
  
  <pre><code>System.ComponentModel.Composition.CompositionException: The composition produced a single composition error. The root cause is provided below. Review the CompositionException.Errors property for more detailed information.
  
  1) The current type,    SquaredInfinity.Foundation.Configuration.Services.IConfigurationService, is an interface and cannot be constructed. Are you missing a type mapping?
  Resulting in: Resolution of the dependency failed, type = "SquaredInfinity.Foundation.Configuration.Services.IConfigurationService", name = "(none)".
  Exception occurred while: while resolving.
  Exception is: InvalidOperationException - The current type, SquaredInfinity.Foundation.Configuration.Services.IConfigurationService, is an interface and cannot be constructed. Are you missing a type mapping?
  -----------------------------------------------
  At the time of the exception, the container was:
    Resolving SquaredInfinity.Foundation.Configuration.Services.IConfigurationService,(none)
  
  Resulting in: An exception occurred while trying to create an instance of type '#Btb.#Rtb'.
  
  Resulting in: Cannot activate part '#Btb.#Rtb'.
  Element: #Btb.#Rtb --&gt;  #Btb.#Rtb
  
  Resulting in: Cannot get export '#Btb.#Rtb (ContractName="Microsoft.VisualStudio.Text.Classification.IClassifierProvider")' from part '#Btb.#Rtb'.
  Element: #Btb.#Rtb (ContractName="Microsoft.VisualStudio.Text.Classification.IClassifierProvider") --&gt;  #Btb.#Rtb
  
     at System.ComponentModel.Composition.Hosting.CompositionServices.GetExportedValueFromComposedPart(ImportEngine engine, ComposablePart part, ExportDefinition definition)
     at System.ComponentModel.Composition.Hosting.CatalogExportProvider.GetExportedValue(CatalogPart part, ExportDefinition export, Boolean isSharedPart)
     at System.ComponentModel.Composition.Hosting.CatalogExportProvider.CatalogExport.GetExportedValueCore()
     at System.ComponentModel.Composition.Primitives.Export.get_Value()
     at System.ComponentModel.Composition.ExportServices.GetCastedExportedValue[T](Export export)
     at System.ComponentModel.Composition.ExportServices.&lt;&gt;c__DisplayClass4`2.&lt;CreateStronglyTypedLazyOfTM&gt;b__1()
     at System.Lazy`1.CreateValue()
     at System.Lazy`1.LazyInitValue()
     at System.Lazy`1.get_Value()
     at Microsoft.VisualStudio.Text.Utilities.GuardedOperations.InvokeMatchingFactories[TExtensionInstance,TExtensionFactory,TMetadataView](IEnumerable`1 lazyFactories, Func`2 getter, IContentType dataContentType, Object errorSource)
  </code></pre>
  
  <p>How do I interpret this so that I can figure out the error?</p>