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Known Error Messages

RadUpload has been replaced by RadAsyncUpload, Telerik’s next-generation ASP.NET upload component. If you are considering Telerik’s Upload control for new development, check out the documentation of RadAsyncUpload or the control’s product page. 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. The official support for RadUpload has been discontinued in June 2013 (Q2’13), although it is still be available in the suite. We deeply believe that RadAsyncUpload can better serve your upload needs and we kindly ask you to transition to it to make sure you take advantage of its support and the new features we constantly add to it.


When you try to use the RadUpload or a standard HtmlInputFile control to upload a large file, the file may not be uploaded.


This problem occurs because the default value for the maxRequestLength parameter in the section of the Machine.config file is 4096 (4 megabytes). As a result, files that are larger than this value are not uploaded by default.


Follow the instructions to configure your application for uploading large files.


You may notice the following error messages if you encounter file size limits during the file upload process:

  • "The page cannot be displayed".

  • "Maximum request length exceeded."

  • "Server Application is Unavailable" In the event log, the error message will be similar to the following: aspnet_wp.exe (PID:PIDNumber) was recycled because memory consumption exceeded the SizeLimit MB (Percentage percent of available RAM).

  • "Exception of type System.OutOfMemoryException was thrown".

You may also find that uploads occur very slowly. If you watch the Aspnet_wp.exe process in Windows Task Manager, you will notice that the memory delta changes by 64 KB every 1 to 2 seconds. Depending on the size of the file, this delay may cause the ASP.NET worker process to recycle because of a responseDeadlock error.

PRB: Cannot Upload Large Files When You Use the HtmlInputFile Server Control

See Also

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