ASMX web service giving an error on when hosted on IIS 7.5

Hi,

I have asmx web service in .net framework 2.0.

When service is hosted on windows server 2003 R2 machine IIS 6.0, I can invoke service method and get appropriate response.

But when I hosted this webservice on windows server 2008 R2 having IIS 7.5, and tried consuming it. I got the following error

The content type text/html; charset=utf-8 of the response message does not match the content type of the binding (text/xml; charset=utf-8). If using a custom encoder, be sure that the IsContentTypeSupported method is implemented properly. The first 1024 bytes of the response were:

The content and the structure of the folders is exactly same.

I am getting following warning in event viewer 

Exception information:

    Exception type: HttpException

    Exception message: Response is not available in this context.

Request information:

    Request URL: http://test.iononline.com/sso.asmx

    Request path: /sso.asmx

    User host address: 10.212.16.4

    User: 

    Is authenticated: False

    Authentication Type: 

    Thread account name: IIS APPPOOL\V20AppPool

Thread information:

    Thread ID: 5

    Thread account name: IIS APPPOOL\V20AppPool

    Is impersonating: False

    Stack trace:    at System.Web.HttpApplicationFactory.EnsureAppStartCalledForIntegratedMode(HttpContext context, HttpApplication app)

   at System.Web.HttpApplication.RegisterEventSubscriptionsWithIIS(IntPtr appContext, HttpContext context, MethodInfo[] handlers)

   at System.Web.HttpApplication.InitSpecial(HttpApplicationState state, MethodInfo[] handlers, IntPtr appContext, HttpContext context)

   at System.Web.HttpApplicationFactory.GetSpecialApplicationInstance(IntPtr appContext, HttpContext context)

   at System.Web.HttpApplicationFactory.GetPipelineApplicationInstance(IntPtr appContext, HttpContext context)

   at System.Web.Hosting.PipelineRuntime.InitializeApplication(IntPtr appContext)

Kindly let me know where I am going wrong. 

Thanks

Siddhesh