1. Did you managed to run your project locally and to have the upload working?
2. Basically to move the upload to the remote server you should just do the following steps:
- change the UploadServiceUrl property
- create the physical folder on your remote server and give the appropriate permissions.
- upload the needed dlls to the remote server - both the Silverlight dlls and the Dll needed for the Upload handler - Telerik.Windows.RadUploadHandler.dll
PS: From the error that you reported the most obvious reason is that the "Telerik.Windows.RadUploadHandler.dll" is missing.
Please confirm that these steps above are ok and, if they are we, will search the problem somewhere else.
the Telerik team
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