AsyncUpload Handler Exeption

36 posts, 0 answers
  1. Nick Jacka
    Nick Jacka avatar
    4 posts
    Member since:
    Jan 2010

    Posted 24 Jun 2012 Link to this post

    Hi all,

    Was just following this thread and thought my recent experience would help other in the future.

    I recently implemented the RadAsyncUpload (Telerik.Web.UI 2012.1.411.35) control in one of my websites and every thing was working fine with it on my development machine (Win7 64-bit with IIS7) and a test server running IIS6, but when I deployed the website to a production server the RadAsyncUpload started to have a problem when selecting file with the following error in the server's event viewer:

    Event code: 4011

    Event message: An unhandled access exception has occurred.

    Event time: 25/06/2012 10:06:14 AM

    Event time (UTC): 25/06/2012 12:06:14 AM

    Event ID: bb378c76a2074ebcbec7f67b8f3dfd0e

    Event sequence: 22

    Event occurrence: 1

    Event detail code: 0

    Application information:

    Application domain: /LM/W3SVC/2/ROOT-3-129850563420767806

    Trust level: Full

    Application Virtual Path: /

    Application Path: C:\inetpub\wwwroot\abs\ips\

    Machine name: AUSYDWSCFT01

    Process information:

    Process ID: 1436

    Process name: w3wp.exe

    Account name: IIS APPPOOL\abs

    Request information:

    Request URL: http://localhost:1080/Telerik.Web.UI.WebResource.axd?type=rau

    Request path: /Telerik.Web.UI.WebResource.axd

    User host address: ::1


    Is authenticated: False

    Authentication Type:

    Thread account name: IIS APPPOOL\abs

    When I attempted to execute the url http://localhost:1080/Telerik.Web.UI.WebResource.axd?type=rau directly I got the message:

    { "message" : "RadAsyncUpload handler is registered succesfully, however, it may not be accessed directly." }

    After looking around at the sites IIS settings on the server for a while I directed my attention to the security privileges of the websites directory and found that giving the IIS_IUSRS account Write access resolved the issue. I'm not sure how this goes with general website directory security policies and if Telerik can provide a better way of providing the correct access privileges to the RadAsyncUpload function on the server-side (maybe through a web.config setting) I would welcome the feedback.


  2. Peter Filipov
    Peter Filipov avatar
    1028 posts

    Posted 27 Jun 2012 Link to this post

    Hi Nick,

    Could you please clarify that you experience the issue on every upload when the IIS_IUSRS user has no write permissions. We still cannot reproduce the could give us more details about your environment (IIS and browser version).
    IIS_IUSRS is given to the user with anonymous authentication. In case that the control is accessed by anonymous user with no write permissions it should be not possible to upload files.

    All the best,
    Peter Filipov
    the Telerik team
    If you want to get updates on new releases, tips and tricks and sneak peeks at our product labs directly from the developers working on the RadControls for ASP.NET AJAX, subscribe to their blog feed now.
  3. Chris
    Chris avatar
    2 posts
    Member since:
    Sep 2012

    Posted 02 Oct 2012 Link to this post

    I was able to reproduce the problem.  It appears for me with windows authentication.  The only access I had to change was the RadUploadTemp folder created in app_data to allow write access to the appropriate users.  The error messages and returns make you think it is the dll.  In order to reproduce it you must be a different user than the person who configured the website.  Since of course they will have access to the folder.

  4. Shukhrat Nekbaev
    Shukhrat Nekbaev avatar
    73 posts
    Member since:
    Oct 2010

    Posted 02 Oct 2012 Link to this post

    Hi Chris,

    not a solution, but a useful (maybe) hint. Personally I use VS' s publish feature, so that it first deletes everything and only then publishes, as soon as my "temp" folders were deleted and/or I needed grant write permissions everytime, I decided to create a folder "RadUploadTemp" outside the webapplication, and in IIS map it as virtual directory "RadUploadTemp" for that application. So basically you need to setup (create/permissions) it one time only and tell all radAsyncUploads to use it in web.config appSettings:
    <add key="Telerik.AsyncUpload.TemporaryFolder" value="~/RadUploadTemp" />

    Imho, eases "tmp" folder issue, if you have such control permissions on the server of course.

    You can deny access to it from outside in web.config:

    <location path="RadUploadTemp">
            <deny users="*" />

    YOUNGKON avatar
    4 posts
    Member since:
    Jan 2014

    Posted 22 Apr 2014 in reply to Dobromir Link to this post

    Hi Admin,

    I'm getting same error as above... View my attachment.


    { "message" : "RadAsyncUpload handler is registered succesfully, however, it may 
    not be accessed directly." }

    How to resolve this

  6. Genady Sergeev
    Genady Sergeev avatar
    1600 posts

    Posted 25 Apr 2014 Link to this post


    This error is presented when one tries to access the RadAsyncUpload handler directly. Please don't access the handler directly.

    If you did not explicitly requested the handler can you elaborate a bit more on how did the issue happened?

    Genady Sergeev

    Check out the Telerik Platform - the only platform that combines a rich set of UI tools with powerful cloud services to develop web, hybrid and native mobile apps.

Back to Top