finally its resolved by using,

<system.webServer>
<validation validateIntegratedModeConfiguration=”false” />
<modules>
<add name=”ScriptModule” preCondition=”integratedMode” type=”System.Web.Handlers.ScriptModule, System.Web.Extensions, Version=1.0.61025.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35″ />
</modules>
<handlers>
<remove name=”WebServiceHandlerFactory-Integrated” />

<add verb=”POST,GET” name=”Ajax” path=”ajax/*.ashx” type=”Ajax.PageHandlerFactory, Ajax” />
<add name=”ScriptHandlerFactory” verb=”*” path=”*.asmx” preCondition=”integratedMode” type=”System.Web.Script.Services.ScriptHandlerFactory, System.Web.Extensions, Version=1.0.61025.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35″ />
<add name=”ScriptHandlerFactoryAppServices” verb=”*” path=”*_AppService.axd” preCondition=”integratedMode” type=”System.Web.Script.Services.ScriptHandlerFactory, System.Web.Extensions, Version=1.0.61025.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35″ />
<add name=”ScriptResource” preCondition=”integratedMode” verb=”GET,HEAD” path=”ScriptResource.axd” type=”System.Web.Handlers.ScriptResourceHandler, System.Web.Extensions, Version=1.0.61025.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35″ />
</handlers>
</system.webServer>

<system.web>
<httpHandlers>
<add verb=”POST,GET” path=”ajax/*.ashx” type=”Ajax.PageHandlerFactory, Ajax”/>
</httpHandlers>
</system.web>