Hi chi,
Sorry for the delay in responding.
How to display a diagram (.edd) in a diagram web controlThe DiagramWebControl uses a custom HTTP handler for processing client requests for rendering the diagram image on to the web page.
Please add the following HTTP handler in your web.config file:
[Web.Config]
$httpHandlers>
$add verb="*" path="diagram_renderer.aspx" type="Syncfusion.Web.UI.WebControls.Diagram.DiagramRenderHandler, Syncfusion.diagram.web, Version=5.102.0.51, culture=Neutral,PublicKeyToken=3d67ed1f87d44c89"/>
$add verb="*" path="samplebrowser.ashx" type="SourceCodeTab.SourceHandler,SourceCodeTab,Version=5.102.0.51, culture=Neutral,PublicKeyToken=3d67ed1f87d44c89"/>
$/httpHandlers>
Note: We have used "$" symbol instead of "<".
Please refer the sample in the below link which illustrates the above:
http://www.syncfusion.com/support/user/uploads/69758_c8aba14d.zipPlease let me know if you have any concerns.
Regards,
Yavana.G