Troubleshoot RadAsyncUpload handler error

[Mark]

How do I trouble shoot the following error "RadAsyncUpload handler is registered successfully, however, it may not be accessed directly."

 

It works fine locally but not on the server.

 

 

 

[Rumen]

The "RadAsyncUpload handler is registered successfully, however, it may not be accessed directly." message when accessing the handler directly from the browser address bar is expected and intentionally designed like this. To facilitate the developers the GET request to the handler returns a human-readable text to notify that the correct handler URL is used and to confirm that the handler is registered successfully.

Can you please provide more information about the server problem?

Do you get any JavaScript or server errors?

Does the AsyncUpload control load on the page?

What happens when you try to upload a file? 

What is different between the developer and production servers?

[Mark]

Can you please provide more information about the server problem?  This looks like a server issue, maybe permissions. It works fine on the local dev PC, just not on the server.

Do you get any JavaScript or server errors? No, not an the initial page load

Does the AsyncUpload control load on the page? Yes

What happens when you try to upload a file? The file color icon goes from yellow to red. On my local PC it goes right to green

What is different between the developer and production servers? It works fine on my local machine just not on the windows server

[Rumen]

If you get the "failed to load resource: the server responded with a status of 500 (internal server error)" error please check these resources on the topic:

• https://docs.telerik.com/devtools/aspnet-ajax/knowledge-base/server-error-500-occurs 
• https://stackoverflow.com/questions/20170482/radasyncupload-throws-http-500-with-a-red-dot-beside-the-uploaded-file-name/20171614 
• https://www.telerik.com/forums/500-error-on-upload 

Also,

• Make sure that the Telerik.Web.UI.WebResource.axd is properly registered in the web.config of the deployed application. You can see all mandatory web.config settings here:
  https://docs.telerik.com/devtools/aspnet-ajax/general-information/web-config-settings-overview#mandatory-additions-to-the-webconfig
• Make sure that the application has full read and write permissions to the Temp folder
• In case you are using authentication, make sure that the RadAsyncUpload handler is excluded from it as demonstrated here:
  
• <location path="Telerik.Web.UI.WebResource.axd">  
      <system.web>      
          <authorization>
              <allow users="*" />      
          </authorization>  
      </system.web>
  </location>
• In addition, I would also advise that you take a look at the Troubleshooting section of RadAsyncUpload and see if any of the suggestions there will help for your case: https://docs.telerik.com/devtools/aspnet-ajax/general-information/web-config-settings-overview#mandatory-additions-to-the-webconfig
• If it is an Azure app: You can temporarily enable the custom errors so you can see a detailed stack trace. This should direct you to what is causing the issue and what a possible solution would be. We have received a number of similar reports where the Azure firewall (WAF - Web Application Firewall) was blocking the web resource requests or modifying the query parameters. You can check with your Network administrators which settings exactly are affecting the web resource requests and tweak them so the application can function properly.

 

[Mark]

The issue was the RadUploadTemp folder under App_Data needed to have the servers IIS_IUSRS added to the folder permissions.

[Rumen]

I am glad that the issues is resolved! Thank you for sharing what was the reason for the problem!