The progress area with RadUpload control in web garden is not supported scenario
If you are using the RadAsyncUpload control everything should be working correct. The only limitation is when IFrame module is used to upload files. The IFrame module is used only in IE browsers when there is no Silverlight or Flash installed. Could you please check which module is used in your application (with right button click on the input)? Also please try to run your project under Firefox and see how it behaves.
All the best,
the Telerik team
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