Upgrade of web site from .Net 2 to 4.5 breaks asmx web services

Despite my best Googling, nobody seems to have had quite this problem (and written about it).

I’m migrating a .Net 2 web site to .Net 4.5 (well, 4.5.1 to be precise). Everything seemed to work except browsing to the .asmx (web service) pages, which threw a System.BadImageFormatException: Invalid token error:

Error Stack:System.InvalidOperationException: Failed to handle request. —> System.InvalidOperationException: Unable to handle request. —> System.Configuration.ConfigurationErrorsException: Invalid token. —> System.BadImageFormatException: Invalid token.
at System.Reflection.RuntimeAssembly._nLoad(AssemblyName fileName, String codeBase, Evidence assemblySecurity, RuntimeAssembly locationHint, StackCrawlMark& stackMark, IntPtr pPrivHostBinder, Boolean throwOnFileNotFound, Boolean forIntrospection, Boolean suppressSecurityChecks)
at System.Reflection.RuntimeAssembly.nLoad(AssemblyName fileName, String codeBase, Evidence assemblySecurity, RuntimeAssembly locationHint, StackCrawlMark& stackMark, IntPtr pPrivHostBinder, Boolean throwOnFileNotFound, Boolean forIntrospection, Boolean suppressSecurityChecks)
at System.Reflection.RuntimeAssembly.InternalLoadAssemblyName(AssemblyName assemblyRef, Evidence assemblySecurity, RuntimeAssembly reqAssembly, StackCrawlMark& stackMark, IntPtr pPrivHostBinder, Boolean throwOnFileNotFound, Boolean forIntrospection, Boolean suppressSecurityChecks)
at System.Reflection.RuntimeAssembly.InternalLoad(String assemblyString, Evidence assemblySecurity, StackCrawlMark& stackMark, IntPtr pPrivHostBinder, Boolean forIntrospection)
at System.Reflection.RuntimeAssembly.InternalLoad(String assemblyString, Evidence assemblySecurity, StackCrawlMark& stackMark, Boolean forIntrospection)
at System.Reflection.Assembly.Load(String assemblyString)
at System.Web.Configuration.CompilationSection.LoadAssemblyHelper(String assemblyName, Boolean starDirective)
— End of inner exception stack trace —
at System.Web.Configuration.CompilationSection.LoadAssemblyHelper(String assemblyName, Boolean starDirective)
at System.Web.Configuration.CompilationSection.LoadAllAssembliesFromAppDomainBinDirectory()
at System.Web.Configuration.CompilationSection.LoadAssembly(AssemblyInfo ai)
at System.Web.Compilation.BuildManager.GetReferencedAssemblies(CompilationSection compConfig)
at System.Web.Compilation.WebDirectoryBatchCompiler..ctor(VirtualDirectory vdir)
at System.Web.Compilation.BuildManager.BatchCompileWebDirectoryInternal(VirtualDirectory vdir, Boolean ignoreErrors)
at System.Web.Compilation.BuildManager.BatchCompileWebDirectory(VirtualDirectory vdir, VirtualPath virtualDir, Boolean ignoreErrors)
at System.Web.Compilation.BuildManager.CompileWebFile(VirtualPath virtualPath)
at System.Web.Compilation.BuildManager.GetVPathBuildResultInternal(VirtualPath virtualPath, Boolean noBuild, Boolean allowCrossApp, Boolean allowBuildInPrecompile, Boolean throwIfNotFound, Boolean ensureIsUpToDate)
at System.Web.Compilation.BuildManager.GetVPathBuildResultWithNoAssert(HttpContext context, VirtualPath virtualPath, Boolean noBuild, Boolean allowCrossApp, Boolean allowBuildInPrecompile, Boolean throwIfNotFound, Boolean ensureIsUpToDate)
at System.Web.Compilation.BuildManager.GetVPathBuildResult(HttpContext context, VirtualPath virtualPath, Boolean noBuild, Boolean allowCrossApp, Boolean allowBuildInPrecompile, Boolean ensureIsUpToDate)
at System.Web.UI.PageParser.GetCompiledPageInstance(VirtualPath virtualPath, String inputFile, HttpContext context)
at System.Web.UI.PageParser.GetCompiledPageInstance(String virtualPath, String inputFile, HttpContext context)
at System.Web.Services.Protocols.DocumentationServerProtocol.GetCompiledPageInstance(String virtualPath, String inputFile, HttpContext context)
at System.Web.Services.Protocols.DocumentationServerProtocol.Initialize()
at System.Web.Services.Protocols.ServerProtocolFactory.Create(Type type, HttpContext context, HttpRequest request, HttpResponse response, Boolean& abortProcessing)
— End of inner exception stack trace —
at System.Web.Services.Protocols.ServerProtocolFactory.Create(Type type, HttpContext context, HttpRequest request, HttpResponse response, Boolean& abortProcessing)
at System.Web.Services.Protocols.WebServiceHandlerFactory.CoreGetHandler(Type type, HttpContext context, HttpRequest request, HttpResponse response)
— End of inner exception stack trace —
at System.Web.Services.Protocols.WebServiceHandlerFactory.CoreGetHandler(Type type, HttpContext context, HttpRequest request, HttpResponse response)
at System.Web.Services.Protocols.WebServiceHandlerFactory.GetHandler(HttpContext context, String verb, String url, String filePath)
at System.Web.Script.Services.ScriptHandlerFactory.GetHandler(HttpContext context, String requestType, String url, String pathTranslated)
at System.Web.HttpApplication.MaterializeHandlerExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute()
at System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously)| Global.asax:Application_Error()

I tried adjusting the .Net version — turns out it would work fine in 3.5 or lower, but broke in 4 or higher.

My machine itself was okay — creating a new 4.5 web site with just a web service in it worked fine.

In the end the solution was to create a new web site and add the individual pages back into it, leaving out the Bin directory. I rebuilt that by adding references to the various DLLs back one by one. Something in the old Bin directory apparently was throwing it out.

0saves
If you enjoyed this post, please consider leaving a comment or subscribing to the RSS feed to have future articles delivered to your feed reader.