如何解决：系统找不到指定的文件。 (异常来自 HRESULT:0x80070002)

IIS7勿然出现这个问题，困扰了我两天了，急啊！！
详细错误信息：
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系统找不到指定的文件。 (异常来自 HRESULT:0x80070002)

说明: 执行当前 Web 请求期间，出现未处理的异常。请检查堆栈跟踪信息，以了解有关该错误以及代码中导致错误的出处的详细信息。

异常详细信息: System.IO.FileNotFoundException: 系统找不到指定的文件。 (异常来自 HRESULT:0x80070002)

源错误:

执行当前 Web 请求期间生成了未处理的异常。可以使用下面的异常堆栈跟踪信息确定有关异常原因和发生位置的信息。

堆栈跟踪:


[FileNotFoundException: 系统找不到指定的文件。 (异常来自 HRESULT:0x80070002)]
System.Reflection.Assembly._nLoad(AssemblyName fileName, String codeBase, Evidence assemblySecurity, Assembly locationHint, StackCrawlMark& stackMark, Boolean throwOnFileNotFound, Boolean forIntrospection) +0
System.Reflection.Assembly.nLoad(AssemblyName fileName, String codeBase, Evidence assemblySecurity, Assembly locationHint, StackCrawlMark& stackMark, Boolean throwOnFileNotFound, Boolean forIntrospection) +43
System.Reflection.Assembly.InternalLoad(AssemblyName assemblyRef, Evidence assemblySecurity, StackCrawlMark& stackMark, Boolean forIntrospection) +127
System.Reflection.Assembly.InternalLoad(String assemblyString, Evidence assemblySecurity, StackCrawlMark& stackMark, Boolean forIntrospection) +142
System.Reflection.Assembly.Load(String assemblyString) +28
System.Web.Configuration.CompilationSection.LoadAssemblyHelper(String assemblyName, Boolean starDirective) +46

[ConfigurationErrorsException: 系统找不到指定的文件。 (异常来自 HRESULT:0x80070002)]
System.Web.Configuration.CompilationSection.LoadAssemblyHelper(String assemblyName, Boolean starDirective) +613
System.Web.Configuration.CompilationSection.LoadAssembly(AssemblyInfo ai) +57
System.Web.Compilation.BuildManager.GetReferencedAssemblies(CompilationSection compConfig) +178
System.Web.Compilation.BuildProvidersCompiler..ctor(VirtualPath configPath, Boolean supportLocalization, String outputAssemblyName) +54
System.Web.Compilation.CodeDirectoryCompiler.GetCodeDirectoryAssembly(VirtualPath virtualDir, CodeDirectoryType dirType, String assemblyName, StringSet excludedSubdirectories, Boolean isDirectoryAllowed) +600
System.Web.Compilation.BuildManager.CompileCodeDirectory(VirtualPath virtualDir, CodeDirectoryType dirType, String assemblyName, StringSet excludedSubdirectories) +125
System.Web.Compilation.BuildManager.CompileCodeDirectories() +265
System.Web.Compilation.BuildManager.EnsureTopLevelFilesCompiled() +320

[HttpException (0x80004005): 系统找不到指定的文件。 (异常来自 HRESULT:0x80070002)]
System.Web.Compilation.BuildManager.ReportTopLevelCompilationException() +58
System.Web.Compilation.BuildManager.EnsureTopLevelFilesCompiled() +512
System.Web.Hosting.HostingEnvironment.Initialize(ApplicationManager appManager, IApplicationHost appHost, IConfigMapPathFactory configMapPathFactory, HostingEnvironmentParameters hostingParameters) +729

[HttpException (0x80004005): 系统找不到指定的文件。 (异常来自 HRESULT:0x80070002)]
System.Web.HttpRuntime.FirstRequestInit(HttpContext context) +8901019
System.Web.HttpRuntime.EnsureFirstRequestInit(HttpContext context) +85
System.Web.HttpRuntime.ProcessRequestNotificationPrivate(IIS7WorkerRequest wr, HttpContext context) +333

版本信息: Microsoft .NET Framework 版本:2.0.50727.4952; ASP.NET 版本:2.0.50727.4955