I found a strange behavior of RadUpload for Silverlight. For testing purposes I have created a small project which contains just a RadUpload control. Uploading files works as expected but when I try to upload a file which has already been uploaded an exception is thrown ("The given key was not present in the dictionary").
When I delete the file from the uploaded files folder, I can upload it again without any problems.
What could be wrong here? What would happen if defferent users try to upload a file with the same name?