DocumentManager uploading file exception: Could not find file

[Sheng]

I'm using Q2 2015 (2015.2.826.45). The code uses RadEditor -> DocumentManager to do the file uploading. The function had been working good without any issue. But recently the code will throw exception when uploading a file. The error message is: 

    System.IO.FileNotFoundException: Could not find file 'C:\inetpub\...\App_Data\RadUploadTemp\1661261184840UploadTest.pdf.tmp'.

Did investigation. I can see that the temp file has been uploaded into the temp folder on server. However, once clicked the button “Upload” on the Upload dialog, the exception happened. I can see that after clicking the button “Upload”, the temp file was gone, but somehow the uploaded file was not moved to the target folder. It seems there's duplicate request happening which caused this exception. The exception happens on all browser (IE11, Edge and Chrome). What might be the reason?

[Rumen]

Hi Sheng,

Please note that version 2015.2.826.45 is vulnerable to CVE-2019-18935 and we strongly recommend upgrading to at least 2020.1.114 or even better the latest one 2022.2.622 as instructed at Allows JavaScriptSerializer Deserialization.

If you still experience the problem, you can set EnableAsyncUpload="false" and test again.

If you prefer to use RadAsyncUpload, could you please make some more tests and check if you can see some consistency on the issue? For example:

• Do you see the issue uploading the same exact file or a specific file type?
• Do you see this error when doing a postback soon after the file is uploaded? If you wait a long time, more than the temp file expiration time, the file would be automatically deleted. 
• Do you see this error in a load-balancing environment? If you do, there might be a chance the temp file is on a different node than the one the postback is looking for it. To fix this, you might need to ensure all nodes have a shared Cache and temporary folder:
• https://www.telerik.com/blogs/integrate-radcontrols-for-asp.net-ajax-in-a-webfarm-or-webgarden