Authentication problem with Upload ( getting 401 )

[Naveen]

Hi,

We get the error 'Handler not found or execution of the handler failed!' error when we hit the upload button with a yellow triangle in the file name box.

We have the handler sitting on a different server. But we have clientaccesspolicy and crossdomain files on it. so it shouldne be a issue.

We get this error ocassionally and not always. I assume it should prompt for credentials since it is sitting on the other server and it should work always once we enter the credentials. But we get prompted for credentials occasionally and thats when it works fine. But rest of the times it doesnt prompt for credentials and get a 401 when looked at fiddler logs. Also this happens from only some of the client machines.

Could you please let me know if it is a known problem or do we need to do any configuration in IE etc.

Thanks,
Naveen.

[Alex Fidanov]

Hello Naveen,

We have not encountered such issue so far. Can you please provide more details on the setup/environment which this issue occurs in? Moreover, you might also find this article helpful regarding cross-domain scenarios and RadUpload.

Best wishes,
Alex Fidanov
the Telerik team

[Naveen]

Hi Alex,
I did check the clientaccess and crossdomain files. they seem to be ok. so here is the scenario:
1. RadUpload handler is hosted on a serverA in a network.
2. Upload Control is hosted in Silverlight in Sharepoint on a serverB in the same network but a different domain as ServerA
3. Users try to access the Upload control from outside the network by conneting using VPN.
4. Ideally when the users try to access, it should prompt once for credentials and it should work fine later on but whenever it prompts for credentials, it works fine. But sometimes all of a sudden we see this issue and when i trace the logs, its just 401s.
5. so i think the issue is its not prompting for authentication all the time or not remebering the credentils after authenticating once.

Let me know in case you want any more details.

Thanks,
Naveen,

[Tina Stancheva]

Hi Naveen,

What is the server's version where the RadUpload and RadUploadHandler are hosted? There were reported issues with a "Handler Not Found" exception in Windows Server 2008R2 which were related to the server's configurations. Also, you can check out this forum, it might also help.

Any additional information that you might give us will be helpful.

Regards,
Tina Stancheva
the Telerik team

[Naveen]

Hi Tina,

RadUploadHandler is hosted in a server which has windows server 2003 SP2 in a 32 bit.
RadUpload( Silverlight ) is hosted in sharepoint which has windows server 2003 SP2 in a 64 bit.

But, because SL runs in client, does the customer OS also matter?
Also as i said before, we dont see the issue all the time. Once it prompts for credentials, it works fine and some how loses the connection again i guess.

Thanks,
Naveen.

[Tina Stancheva]

Hi Naveen,

We did our best to reproduce the problem on our side, but to no avail. We really shoot in the dark here and we ran out of ideas what might be causing the problem. The fact that everything works as expected on our end makes us believe that the source of the problem lies somewhere outside the logic and behavior of the RadUpload.

This is the list of the most common issues that our clients usually encounter with the RadUpload. Can you make sure that in the cases when the issue is reproducible the reason isn't related to the scenarios described in that list.

Also, from what you shared with us, it seems that whenever the user has the right credentials, the UplaodHandler can be reached. Is it possible during the VPN session those credentials to be lost due to connection errors?

All the best,
Tina Stancheva
the Telerik team