In order to get the RadChart charting controls to work correctly in DotNetNuke you must first take into account that DNN rewrites all URLs to what are called ‘Pretty URLs’. Because of this the RadChart has a hard time locating the URL of the HttpHandler which creates the chart images.
To fix this you need to help the RadChart instance out by telling it where the HttpHandler URL is. This can be done by setting the HttpHandler URL through the RadChart’s HttpHandlerUrl property in the Page Load event of your DNN module control as shown below.
myRadChartInstance.HttpHandlerUrl = ResolveUrl("ChartImage.axd") ;
MemoryTin 
I'm interested in Telerik Control Usage together with DotNetNuke. If you have any suggestions of how it can be efficiently done – please let me know.
I have created a module (XsltDb) that allows us to instantiate telerik controls, please review.
http://xsltdb.com/Tree/RadTreeView.aspx
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Hi schleichermann,
Thank you very very much for putting this in your blog! I've spend already 2 hours in figuring out why it was'nt working correct and i assumed it had to do with the axd.
Just tried your suggestion and it works perfect!!
djebe
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