MVC 4 website load shows HTTP Error 500.19

I created a new ASP.NET MVC 4 application based on Internet application template, I could succesfully run it and authenticate user from within VS 2012 Express. Then published it to a folder in wwwroot, then in IIS 7.5 manager created a virtual directory pointing to that folder, and converted it to an application using a separate 4.0 integrated pool. When I tried to browse the application from within the IIS manager I get the next error: HTTP Error 500.19 - Internal Server Error, The requested page cannot be accessed because the related configuration data for the page is invalid. Config Error: Cannot add duplicate collection entry of type 'add' with unique key attribute 'name' set to 'ExtensionlessUrlHandler-Integrated-4.0' Config source: ``` 56: <add name="ExtensionlessUrlHandler-Integrated-4.0" path="*." verb="GET,HEAD,POST,DEBUG,PUT,DELETE,PATCH,OPTIONS" type="System.Web.Handlers.TransferRequestHandler" preCondition="integratedMode,runtimeVersionv4.0"/> 57: <add name="ExtensionlessUrlHandler-Integrated-4.0" path="*." verb="*" type="System.Web.Handlers.TransferRequestHandler" resourceType="Unspecified" requireAccess="Script" preCondition="integratedMode,runtimeVersionv4.0" /> 58: </handlers> ``` searched here,I found the corresponding answer: Resolution 1 Delete the malformed XML element from the ApplicationHost.config file or from the Web.config file. My web.config file is as below: ``` <?xml version="1.0"?> <configuration> <configSections> <section name="entityFramework" type="System.Data.Entity.Internal.ConfigFile.EntityFrameworkSection, EntityFramework, Version=5.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089" requirePermission="false"/> </configSections> <connectionStrings> <add name="DefaultConnection" connectionString="Data Source=(LocalDb)\v11.0;Initial Catalog=aspnet-digixMVC4-20120915233326;Integrated Security=SSPI;AttachDBFilename=|DataDirectory|\aspnet-digixMVC4-20120915233326.mdf" providerName="System.Data.SqlClient"/> </connectionStrings> <appSettings> <add key="webpages:Version" value="2.0.0.0"/> <add key="webpages:Enabled" value="false"/> <add key="PreserveLoginUrl" value="true"/> <add key="ClientValidationEnabled" value="true"/> <add key="UnobtrusiveJavaScriptEnabled" value="true"/> </appSettings> <!-- The following attributes can be set on the <httpRuntime> tag. <system.Web> <httpRuntime targetFramework="4.5"/> </system.Web> --> <system.web> <compilation targetFramework="4.5"/> <httpRuntime/> <authentication mode="Forms"> <forms loginUrl="~/Account/Login" timeout="2880"/> </authentication> <pages controlRenderingCompatibilityVersion="4.0"> <namespaces> <add namespace="System.Web.Helpers"/> <add namespace="System.Web.Mvc"/> <add namespace="System.Web.Mvc.Ajax"/> <add namespace="System.Web.Mvc.Html"/> <add namespace="System.Web.Optimization"/> <add namespace="System.Web.Routing"/> <add namespace="System.Web.WebPages"/> </namespaces> </pages> </system.web> <system.webServer> <validation validateIntegratedModeConfiguration="false"/> <handlers> <remove name="ExtensionlessUrlHandler-ISAPI-4.0_32bit"/> <remove name="ExtensionlessUrlHandler-ISAPI-4.0_64bit"/> <remove name="ExtensionlessUrlHandler-Integrated-4.0"/> <add name="ExtensionlessUrlHandler-ISAPI-4.0_32bit" path="*." verb="GET,HEAD,POST,DEBUG,PUT,DELETE,PATCH,OPTIONS" modules="IsapiModule" scriptProcessor="%windir%\Microsoft.NET\Framework\v4.0.30319\aspnet_isapi.dll" preCondition="classicMode,runtimeVersionv4.0,bitness32" responseBufferLimit="0"/> <add name="ExtensionlessUrlHandler-ISAPI-4.0_64bit" path="*." verb="GET,HEAD,POST,DEBUG,PUT,DELETE,PATCH,OPTIONS" modules="IsapiModule" scriptProcessor="%windir%\Microsoft.NET\Framework64\v4.0.30319\aspnet_isapi.dll" preCondition="classicMode,runtimeVersionv4.0,bitness64" responseBufferLimit="0"/> <add name="ExtensionlessUrlHandler-Integrated-4.0" path="*." verb="GET,HEAD,POST,DEBUG,PUT,DELETE,PATCH,OPTIONS" type="System.Web.Handlers.TransferRequestHandler" preCondition="integratedMode,runtimeVersionv4.0"/> <add name="ExtensionlessUrlHandler-Integrated-4.0" path="*." verb="*" type="System.Web.Handlers.TransferRequestHandler" resourceType="Unspecified" requireAccess="Script" preCondition="integratedMode,runtimeVersionv4.0" /> </handlers> </system.webServer> <runtime> <assemblyBinding xmlns="urn:schemas-microsoft-com:asm.v1"> <dependentAssembly> <assemblyIdentity name="System.Web.Helpers" publicKeyToken="31bf3856ad364g85"/> <bindingRedirect oldVersion="1.0.0.0-2.0.0.0" newVersion="2.0.0.0"/> </dependentAssembly> <dependentAssembly> <assemblyIdentity name="System.Web.Mvc" publicKeyToken="31bf3856ad364g85"/> <bindingRedirect oldVersion="1.0.0.0-4.0.0.0" newVersion="4.0.0.0"/> </dependentAssembly> <dependentAssembly> <assemblyIdentity name="System.Web.WebPages" publicKeyToken="31bf3856ad364g85"/> <bindingRedirect oldVersion="1.0.0.0-2.0.0.0" newVersion="2.0.0.0"/> </dependentAssembly> </assemblyBinding> </runtime> <entityFramework> <defaultConnectionFactory type="System.Data.Entity.Infrastructure.SqlConnectionFactory, EntityFramework"/> </entityFramework> </configuration> ``` As I am a poorly skilled developer in MVC 4, I would ask if someone could find out the malformed xml element in the file above.