在加载我的ASP.NET应用程序/网站时，我得到了这个错误消息：“遇到了异常。这可能是由扩展引起的。”
然后说要查看此文件：
C：\用户\粘土\应用程序数据\漫游\微软\ VisualStudio的\ 11.0 \ ActivityLog.xml
...我确实找到了可能与问题相关的三个条目，但它们是“希腊语给我”。由于它们的大量，我只是在这里包括第一个：
<entry>
<record>676</record>
<time>2013/10/22 13:52:50.109</time>
<type>Error</type>
<source>Editor or Editor Extension</source>
<description>System.ComponentModel.Composition.CompositionException: The composition produced a single composition error, with 2 root causes. The root causes are provided below. Review the CompositionException.Errors property for more detailed information.

1) The export 'Microsoft.VisualStudio.Shell.SVsServiceProvider' is not assignable to type 'System.Void'.

Resulting in: Cannot set import 'Microsoft.VisualStudio.JavaScript.Web.Extensions.Shared.RegistryManager.VsServiceProvider (ContractName="Microsoft.VisualStudio.Shell.SVsServiceProvider")' on part 'Microsoft.VisualStudio.JavaScript.Web.Extensions.Shared.RegistryManager'.
Element: Microsoft.VisualStudio.JavaScript.Web.Extensions.Shared.RegistryManager.VsServiceProvider (ContractName="Microsoft.VisualStudio.Shell.SVsServiceProvider") --> Microsoft.VisualStudio.JavaScript.Web.Extensions.Shared.RegistryManager

Resulting in: Cannot get export 'Microsoft.VisualStudio.JavaScript.Web.Extensions.Shared.RegistryManager (ContractName="Microsoft.VisualStudio.JavaScript.Web.Extensions.Shared.IRegistryManager")' from part 'Microsoft.VisualStudio.JavaScript.Web.Extensions.Shared.RegistryManager'.
Element: Microsoft.VisualStudio.JavaScript.Web.Extensions.Shared.RegistryManager (ContractName="Microsoft.VisualStudio.JavaScript.Web.Extensions.Shared.IRegistryManager") --> Microsoft.VisualStudio.JavaScript.Web.Extensions.Shared.RegistryManager

Resulting in: Cannot set import 'Microsoft.VisualStudio.JavaScript.Web.Extensions.Shared.BufferFeatureManagerProvider.RegistryManager (ContractName="Microsoft.VisualStudio.JavaScript.Web.Extensions.Shared.IRegistryManager")' on part 'Microsoft.VisualStudio.JavaScript.Web.Extensions.Shared.BufferFeatureManagerProvider'.
Element: Microsoft.VisualStudio.JavaScript.Web.Extensions.Shared.BufferFeatureManagerProvider.RegistryManager (ContractName="Microsoft.VisualStudio.JavaScript.Web.Extensions.Shared.IRegistryManager") --> Microsoft.VisualStudio.JavaScript.Web.Extensions.Shared.BufferFeatureManagerProvider

Resulting in: Cannot get export 'Microsoft.VisualStudio.JavaScript.Web.Extensions.Shared.BufferFeatureManagerProvider (ContractName="Microsoft.VisualStudio.JavaScript.Web.Extensions.Shared.IBufferFeatureManagerProvider")' from part 'Microsoft.VisualStudio.JavaScript.Web.Extensions.Shared.BufferFeatureManagerProvider'.
Element: Microsoft.VisualStudio.JavaScript.Web.Extensions.Shared.BufferFeatureManagerProvider (ContractName="Microsoft.VisualStudio.JavaScript.Web.Extensions.Shared.IBufferFeatureManagerProvider") --> Microsoft.VisualStudio.JavaScript.Web.Extensions.Shared.BufferFeatureManagerProvider

Resulting in: Cannot set import 'Microsoft.VisualStudio.JavaScript.Web.Extensions.Classification.SPARegionTaggerProvider.BufferFeatureManagerProvider (ContractName="Microsoft.VisualStudio.JavaScript.Web.Extensions.Shared.IBufferFeatureManagerProvider")' on part 'Microsoft.VisualStudio.JavaScript.Web.Extensions.Classification.SPARegionTaggerProvider'.
Element: Microsoft.VisualStudio.JavaScript.Web.Extensions.Classification.SPARegionTaggerProvider.BufferFeatureManagerProvider (ContractName="Microsoft.VisualStudio.JavaScript.Web.Extensions.Shared.IBufferFeatureManagerProvider") --> Microsoft.VisualStudio.JavaScript.Web.Extensions.Classification.SPARegionTaggerProvider

Resulting in: Cannot get export 'Microsoft.VisualStudio.JavaScript.Web.Extensions.Classification.SPARegionTaggerProvider (ContractName="Microsoft.VisualStudio.Text.Tagging.IViewTaggerProvider")' from part 'Microsoft.VisualStudio.JavaScript.Web.Extensions.Classification.SPARegionTaggerProvider'.
Element: Microsoft.VisualStudio.JavaScript.Web.Extensions.Classification.SPARegionTaggerProvider (ContractName="Microsoft.VisualStudio.Text.Tagging.IViewTaggerProvider") --> Microsoft.VisualStudio.JavaScript.Web.Extensions.Classification.SPARegionTaggerProvider

2) The export 'Microsoft.VisualStudio.Web.Extensions.HTML.TagNameProvider (ContractName="Microsoft.VisualStudio.Web.Extensions.HTML.ITagNameProvider")' is not assignable to type 'System.Void'.

Resulting in: Cannot set import 'Microsoft.VisualStudio.JavaScript.Web.Extensions.Shared.SPASupportedTagSet.TagNameProvider (ContractName="Microsoft.VisualStudio.Web.Extensions.HTML.ITagNameProvider")' on part 'Microsoft.VisualStudio.JavaScript.Web.Extensions.Shared.SPASupportedTagSet'.
Element: Microsoft.VisualStudio.JavaScript.Web.Extensions.Shared.SPASupportedTagSet.TagNameProvider (ContractName="Microsoft.VisualStudio.Web.Extensions.HTML.ITagNameProvider") --> Microsoft.VisualStudio.JavaScript.Web.Extensions.Shared.SPASupportedTagSet

Resulting in: Cannot get export 'Microsoft.VisualStudio.JavaScript.Web.Extensions.Shared.SPASupportedTagSet (ContractName="Microsoft.VisualStudio.JavaScript.Web.Extensions.Shared.ISPASupportedTagProvider")' from part 'Microsoft.VisualStudio.JavaScript.Web.Extensions.Shared.SPASupportedTagSet'.
Element: Microsoft.VisualStudio.JavaScript.Web.Extensions.Shared.SPASupportedTagSet (ContractName="Microsoft.VisualStudio.JavaScript.Web.Extensions.Shared.ISPASupportedTagProvider") --> Microsoft.VisualStudio.JavaScript.Web.Extensions.Shared.SPASupportedTagSet

Resulting in: Cannot set import 'Microsoft.VisualStudio.JavaScript.Web.Extensions.Classification.SPARegionTaggerProvider.TagNameProvider (ContractName="Microsoft.VisualStudio.JavaScript.Web.Extensions.Shared.ISPASupportedTagProvider")' on part 'Microsoft.VisualStudio.JavaScript.Web.Extensions.Classification.SPARegionTaggerProvider'.
Element: Microsoft.VisualStudio.JavaScript.Web.Extensions.Classification.SPARegionTaggerProvider.TagNameProvider (ContractName="Microsoft.VisualStudio.JavaScript.Web.Extensions.Shared.ISPASupportedTagProvider") --> Microsoft.VisualStudio.JavaScript.Web.Extensions.Classification.SPARegionTaggerProvider

Resulting in: Cannot get export 'Microsoft.VisualStudio.JavaScript.Web.Extensions.Classification.SPARegionTaggerProvider (ContractName="Microsoft.VisualStudio.Text.Tagging.IViewTaggerProvider")' from part 'Microsoft.VisualStudio.JavaScript.Web.Extensions.Classification.SPARegionTaggerProvider'.
Element: Microsoft.VisualStudio.JavaScript.Web.Extensions.Classification.SPARegionTaggerProvider (ContractName="Microsoft.VisualStudio.Text.Tagging.IViewTaggerProvider") --> Microsoft.VisualStudio.JavaScript.Web.Extensions.Classification.SPARegionTaggerProvider

 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.<>c__DisplayClass4`2.<CreateStronglyTypedLazyOfTM>b__1()
 at System.Lazy`1.CreateValue()
 at System.Lazy`1.LazyInitValue()
 at System.Lazy`1.get_Value()
 at Microsoft.VisualStudio.Text.Tagging.Implementation.TagAggregator`1.GatherTaggers(ITextBuffer textBuffer)</description>
</entry>
解码错误是：
System.ComponentModel.Composition.CompositionException: The composition produced a single composition error, with 2 root causes. The root causes are provided below. Review the CompositionException.Errors property for more detailed information. 1) The export 'Microsoft.VisualStudio.Shell.SVsServiceProvider' is not assignable to type 'System.Void'. Resulting in: Cannot set import 'Microsoft.VisualStudio.JavaScript.Web.Extensions.Shared.RegistryManager.VsServiceProvider (ContractName="Microsoft.VisualStudio.Shell.SVsServiceProvider")' on part 'Microsoft.VisualStudio.JavaScript.Web.Extensions.Shared.RegistryManager'. Element: Microsoft.VisualStudio.JavaScript.Web.Extensions.Shared.RegistryManager.VsServiceProvider (ContractName="Microsoft.VisualStudio.Shell.SVsServiceProvider") --> Microsoft.VisualStudio.JavaScript.Web.Extensions.Shared.RegistryManager Resulting in: Cannot get export 'Microsoft.VisualStudio.JavaScript.Web.Extensions.Shared.RegistryManager (ContractName="Microsoft.VisualStudio.JavaScript.Web.Extensions.Shared.IRegistryManager")' from part 'Microsoft.VisualStudio.JavaScript.Web.Extensions.Shared.RegistryManager'. Element: Microsoft.VisualStudio.JavaScript.Web.Extensions.Shared.RegistryManager (ContractName="Microsoft.VisualStudio.JavaScript.Web.Extensions.Shared.IRegistryManager") --> Microsoft.VisualStudio.JavaScript.Web.Extensions.Shared.RegistryManager Resulting in: Cannot set import 'Microsoft.VisualStudio.JavaScript.Web.Extensions.Shared.BufferFeatureManagerProvider.RegistryManager (ContractName="Microsoft.VisualStudio.JavaScript.Web.Extensions.Shared.IRegistryManager")' on part 'Microsoft.VisualStudio.JavaScript.Web.Extensions.Shared.BufferFeatureManagerProvider'. Element: Microsoft.VisualStudio.JavaScript.Web.Extensions.Shared.BufferFeatureManagerProvider.RegistryManager (ContractName="Microsoft.VisualStudio.JavaScript.Web.Extensions.Shared.IRegistryManager") --> Microsoft.VisualStudio.JavaScript.Web.Extensions.Shared.BufferFeatureManagerProvider Resulting in: Cannot get export 'Microsoft.VisualStudio.JavaScript.Web.Extensions.Shared.BufferFeatureManagerProvider (ContractName="Microsoft.VisualStudio.JavaScript.Web.Extensions.Shared.IBufferFeatureManagerProvider")' from part 'Microsoft.VisualStudio.JavaScript.Web.Extensions.Shared.BufferFeatureManagerProvider'. Element: Microsoft.VisualStudio.JavaScript.Web.Extensions.Shared.BufferFeatureManagerProvider (ContractName="Microsoft.VisualStudio.JavaScript.Web.Extensions.Shared.IBufferFeatureManagerProvider") --> Microsoft.VisualStudio.JavaScript.Web.Extensions.Shared.BufferFeatureManagerProvider Resulting in: Cannot set import 'Microsoft.VisualStudio.JavaScript.Web.Extensions.Classification.SPARegionTaggerProvider.BufferFeatureManagerProvider (ContractName="Microsoft.VisualStudio.JavaScript.Web.Extensions.Shared.IBufferFeatureManagerProvider")' on part 'Microsoft.VisualStudio.JavaScript.Web.Extensions.Classification.SPARegionTaggerProvider'. Element: Microsoft.VisualStudio.JavaScript.Web.Extensions.Classification.SPARegionTaggerProvider.BufferFeatureManagerProvider (ContractName="Microsoft.VisualStudio.JavaScript.Web.Extensions.Shared.IBufferFeatureManagerProvider") --> Microsoft.VisualStudio.JavaScript.Web.Extensions.Classification.SPARegionTaggerProvider Resulting in: Cannot get export 'Microsoft.VisualStudio.JavaScript.Web.Extensions.Classification.SPARegionTaggerProvider (ContractName="Microsoft.VisualStudio.Text.Tagging.IViewTaggerProvider")' from part 'Microsoft.VisualStudio.JavaScript.Web.Extensions.Classification.SPARegionTaggerProvider'. Element: Microsoft.VisualStudio.JavaScript.Web.Extensions.Classification.SPARegionTaggerProvider (ContractName="Microsoft.VisualStudio.Text.Tagging.IViewTaggerProvider") --> Microsoft.VisualStudio.JavaScript.Web.Extensions.Classification.SPARegionTaggerProvider 2) The export 'Microsoft.VisualStudio.Web.Extensions.HTML.TagNameProvider (ContractName="Microsoft.VisualStudio.Web.Extensions.HTML.ITagNameProvider")' is not assignable to type 'System.Void'. Resulting in: Cannot set import 'Microsoft.VisualStudio.JavaScript.Web.Extensions.Shared.SPASupportedTagSet.TagNameProvider (ContractName="Microsoft.VisualStudio.Web.Extensions.HTML.ITagNameProvider")' on part 'Microsoft.VisualStudio.JavaScript.Web.Extensions.Shared.SPASupportedTagSet'. Element: Microsoft.VisualStudio.JavaScript.Web.Extensions.Shared.SPASupportedTagSet.TagNameProvider (ContractName="Microsoft.VisualStudio.Web.Extensions.HTML.ITagNameProvider") --> Microsoft.VisualStudio.JavaScript.Web.Extensions.Shared.SPASupportedTagSet Resulting in: Cannot get export 'Microsoft.VisualStudio.JavaScript.Web.Extensions.Shared.SPASupportedTagSet (ContractName="Microsoft.VisualStudio.JavaScript.Web.Extensions.Shared.ISPASupportedTagProvider")' from part 'Microsoft.VisualStudio.JavaScript.Web.Extensions.Shared.SPASupportedTagSet'. Element: Microsoft.VisualStudio.JavaScript.Web.Extensions.Shared.SPASupportedTagSet (ContractName="Microsoft.VisualStudio.JavaScript.Web.Extensions.Shared.ISPASupportedTagProvider") --> Microsoft.VisualStudio.JavaScript.Web.Extensions.Shared.SPASupportedTagSet Resulting in: Cannot set import 'Microsoft.VisualStudio.JavaScript.Web.Extensions.Classification.SPARegionTaggerProvider.TagNameProvider (ContractName="Microsoft.VisualStudio.JavaScript.Web.Extensions.Shared.ISPASupportedTagProvider")' on part 'Microsoft.VisualStudio.JavaScript.Web.Extensions.Classification.SPARegionTaggerProvider'. Element: Microsoft.VisualStudio.JavaScript.Web.Extensions.Classification.SPARegionTaggerProvider.TagNameProvider (ContractName="Microsoft.VisualStudio.JavaScript.Web.Extensions.Shared.ISPASupportedTagProvider") --> Microsoft.VisualStudio.JavaScript.Web.Extensions.Classification.SPARegionTaggerProvider Resulting in: Cannot get export 'Microsoft.VisualStudio.JavaScript.Web.Extensions.Classification.SPARegionTaggerProvider (ContractName="Microsoft.VisualStudio.Text.Tagging.IViewTaggerProvider")' from part 'Microsoft.VisualStudio.JavaScript.Web.Extensions.Classification.SPARegionTaggerProvider'. Element: Microsoft.VisualStudio.JavaScript.Web.Extensions.Classification.SPARegionTaggerProvider (ContractName="Microsoft.VisualStudio.Text.Tagging.IViewTaggerProvider") --> Microsoft.VisualStudio.JavaScript.Web.Extensions.Classification.SPARegionTaggerProvider 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.c__DisplayClass4`2.b__1() at System.Lazy`1.CreateValue() at System.Lazy`1.LazyInitValue() at System.Lazy`1.get_Value() at Microsoft.VisualStudio.Text.Tagging.Implementation.TagAggregator`1.GatherTaggers(ITextBuffer textBuffer)
答案 0 :(得分：9)
此错误通常是由缓存的元数据中的损坏引起的。为什么会发生这种情况我不知道，但清除缓存通常会使Visual Studio返回正常工作状态：
然后，当您安装Visual Studio更新1,2,3或4并且具有针对旧版本构建的其他可视演播室部件（如Web工具）时，也会发生此异常。将它们升级到最新版本通常也会有所帮助：