publishing ASP.net project on server -fail

My project is developed on ASP.net with C#. I want to publish my project on our company's server. I have published my project successfully on server.But when I open any aspx page, it is giving me such error. Any Idea? All pages are running very well in my local host.

Server Error in '/' Application. Configuration Error Description: An error occurred during the processing of a configuration file required to service this request. Please review the specific error details below and modify your configuration file appropriately.

Parser Error Message: Sections must only appear once per config file. See the help topic for exceptions.

Source Error:

Line 27: Line 28: Line 29: Line 30: Line 31:

Source File: C:\Documents and Settings\TaxSmart\Desktop\khushubu_ASP\AAS_Application\AAS_Application\web.config Line: 29

Version Information: Microsoft .NET

web.config :

<?xml version="1.0"?>

!--> section enables configuration of the security authentication mode used by ASP.NET to identify an incoming user. --> section enables configuration of what to do if/when an unhandled error occurs during the execution of a request. Specifically, it enables developers to configure html error pages to be displayed in place of a error stack trace.

    <customErrors mode="RemoteOnly" defaultRedirect="GenericErrorPage.htm">
        <error statusCode="403" redirect="NoAccess.htm" />
        <error statusCode="404" redirect="FileNotFound.htm" />
    </customErrors>
    -->
    <pages>
        <controls>
            <add tagPrefix="asp" namespace="System.Web.UI" assembly="System.Web.Extensions, Version=3.5.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35"/>
            <add tagPrefix="asp" namespace="System.Web.UI.WebControls" assembly="System.Web.Extensions, Version=3.5.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35"/>
        </controls>
    </pages>
    <httpHandlers>
        <remove verb="*" path="*.asmx"/>
        <add verb="*" path="*.asmx" validate="false" type="System.Web.Script.Services.ScriptHandlerFactory, System.Web.Extensions, Version=3.5.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35"/>
        <add verb="*" path="*_AppService.axd" validate="false" type="System.Web.Script.Services.ScriptHandlerFactory, System.Web.Extensions, Version=3.5.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35"/>
        <add verb="GET,HEAD" path="ScriptResource.axd" type="System.Web.Handlers.ScriptResourceHandler, System.Web.Extensions, Version=3.5.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35" validate="false"/>
    </httpHandlers>
    <httpModules>
        <add name="ScriptModule" type="System.Web.Handlers.ScriptModule, System.Web.Extensions, Version=3.5.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35"/>
    </httpModules>
</system.web>
<system.codedom>
    <compilers>
        <compiler language="c#;cs;csharp" extension=".cs" warningLevel="4" type="Microsoft.CSharp.CSharpCodeProvider, System, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089">
            <providerOption name="CompilerVersion" value="v3.5"/>
            <providerOption name="WarnAsError" value="false"/>
        </compiler>
    </compilers>
</system.codedom>
<!-- 
    The system.webServer section is required for running ASP.NET AJAX under Internet
    Information Services 7.0.  It is not necessary for previous version of IIS.
-->
<system.webServer>
    <validation validateIntegratedModeConfiguration="false"/>
    <modules>
        <remove name="ScriptModule"/>
        <add name="ScriptModule" preCondition="managedHandler" type="System.Web.Handlers.ScriptModule, System.Web.Extensions, Version=3.5.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35"/>
    </modules>
    <handlers>
        <remove name="WebServiceHandlerFactory-Integrated"/>
        <remove name="ScriptHandlerFactory"/>
        <remove name="ScriptHandlerFactoryAppServices"/>
        <remove name="ScriptResource"/>
        <add name="ScriptHandlerFactory" verb="*" path="*.asmx" preCondition="integratedMode" type="System.Web.Script.Services.ScriptHandlerFactory, System.Web.Extensions, Version=3.5.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35"/>
        <add name="ScriptHandlerFactoryAppServices" verb="*" path="*_AppService.axd" preCondition="integratedMode" type="System.Web.Script.Services.ScriptHandlerFactory, System.Web.Extensions, Version=3.5.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35"/>
        <add name="ScriptResource" preCondition="integratedMode" verb="GET,HEAD" path="ScriptResource.axd" type="System.Web.Handlers.ScriptResourceHandler, System.Web.Extensions, Version=3.5.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35"/>
    </handlers>
</system.webServer>
<runtime>
    <assemblyBinding xmlns="urn:schemas-microsoft-com:asm.v1">
        <dependentAssembly>
            <assemblyIdentity name="System.Web.Extensions" publicKeyToken="31bf3856ad364e35"/>
            <bindingRedirect oldVersion="1.0.0.0-1.1.0.0" newVersion="3.5.0.0"/>
        </dependentAssembly>
        <dependentAssembly>
            <assemblyIdentity name="System.Web.Extensions.Design" publicKeyToken="31bf3856ad364e35"/>
            <bindingRedirect oldVersion="1.0.0.0-1.1.0.0" newVersion="3.5.0.0"/>
        </dependentAssembly>
    </assemblyBinding>
</runtime>
<connectionStrings>
    <add name="AASProject" connectionString="Data Source=182.50.133.145;Database=taxsmartapp;User ID=taxsmartapp ;Password=Admin123! "/>
</connectionStrings>

</connectionStrings>-->

Solution

This implies that you have a section in your web.config/app.config defined more than once, have a check over it for duplicate sections (possibly those which IIS may have inserted for you when configuring the site)