Microsoft Chart Control Sys.WebForms.PageRequestManagerServerErrorException Errro

if you are using the Microsoft Chart control with in Update Panel sometimes its through the following exception
[Exception... "'Sys.WebForms.PageRequestManagerServerErrorException: Sys.WebForms.PageRequestManagerServerErrorException: Error executing child request for ChartImg.axd.' when calling method:

and controls not working properly,

you have to check the following details in your Web.config files
1.httpHandlers
remove name="ChartImageHandler"
add path="ChartImg.axd" verb="GET,HEAD,POST" type="System.Web.UI.DataVisualization.Charting.ChartHttpHandler, System.Web.DataVisualization, Version=3.5.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35" validate="false"/
httpHandlers

2.appSettings
add key="ChartImageHandler" value="Storage=file;Timeout=20;dir=your_sorage_here;"/
/appSettings