In the ticket information you checked RadUpload control. Please note that RadUpload has been replaced by RadAsyncUpload, Telerik’s next-generation ASP.NET upload component. If you are already using RadUpload in your projects, you may be interested in reading how easy the transition to RadAsyncUpload is and how you can benefit from it in this blog post.
If using the RadUpload control is critical for you please review RadUpload get File Name on Client.
If you are using RadAsyncUpload please take a look at Client-Side file size validation in RadAsyncUpload
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