BufferSize property error

4 posts, 0 answers
  1. Maulik Patel
    Maulik Patel avatar
    36 posts
    Member since:
    Mar 2010

    Posted 01 Jun 2012 Link to this post


    We have started facing Uploader error. The error says
    "Handler not found or execution of the handler failed!
    The remote server returned an error: NotFound.
    Check RadUpload's BufferSize property remarks.". 

    I already tried setting up BufferSize property but no luck. Is it something known changed in Q1 2012 release? The same code was working fine.  

    Your quick response would really helpful.

  2. Tina Stancheva
    Tina Stancheva avatar
    3299 posts

    Posted 01 Jun 2012 Link to this post

    Hello Maulik,

    We haven't changed the implementation of the control with the Q1 release and this is why I'm not sure why you're receiving this error now. Basically it indicates that the RadUpload can't reach the RadUploadHandler.

    So if you've defined a relative path to the handler, the Upload control logic will get the url path to the SL XAP file (through Application.Current.Host.Source) and then based on your relative path settings will construct the way to the handler. And this is why you'll need to make sure that the UploadHandler can be reached and accessed through that relative path. Or you can simply provide an absolute URL to the RadUploadHandler in the RadUpload definition.

    Also, we had a few reports indicating that sometimes the relative path isn't correctly constructed when the SL application is published. Even though we weren't able to reproduce such an issue, a few clients reported that they had to create the following logic for constructing the path to the handler:

    //Setup the service URL for uploader
    string sBaseUrl = Application.Current.Host.Source.ToString().ToLower();
    int indexOfClientBin = sBaseUrl.IndexOf("/clientbin");
    sBaseUrl = sBaseUrl.Substring(0, indexOfClientBin);
    radUpload.UploadServiceUrl = sBaseUrl + "/RadUploadHandler.ashx";
    So you can give this a try as well.

    Please let me know if that info helps.

    Tina Stancheva
    the Telerik team

    Explore the entire Telerik portfolio by downloading the Ultimate Collection trial package. Get it now >>

    EDGAR JIMENEZ avatar
    8 posts
    Member since:
    Apr 2010

    Posted 22 Jun 2012 Link to this post

    Hi Tina,

    We are facing a similar problem.  All of our clients are running IE (7 - 9) and using either XP or Vista.  Our application is using Silverlight 5, with the backend running on Windows Server 2008 R2 and IIS 7.5.  We're using the 2012Q1.SP1 release of Telerik Silverlight Controls.

    We've started handling the failed upload by giving the user a prompt that asks them to try again, and the vast majority of the time it works on their second try.  We've been trying different things over the past couple months including these http://www.telerik.com/support/kb/silverlight/upload/troubleshooting-radupload-for-silverlight.aspx and the handler address logic you suggested, but we haven't been able to identify the root cause of the issue and see no downward trend.  Is there any other known issue or a better way to pinpoint where the error is occuring?  Or, is there a way to reattempt the upload automatically for the user?  Currently, we are catching any FileUploadFailedEvents and getting the following information:

    Product Name: MSIE


    Product Version: 8.0


    Name: Microsoft Internet Explorer


    Cookies Enabled: True


    Platform: Win32


    User Agent: Mozilla/4.0 (compatible; MSIE 8.0; Windows NT 5.1; Trident/4.0; STIE60-021004; STIE60-020212; .NET CLR 1.0.3705; .NET CLR 1.1.4322; .NET CLR 2.0.50727; .NET CLR 3.0.04506.30; .NET CLR 3.0.04506.648; InfoPath.2; .NET CLR 3.0.4506.2152; .NET CLR 3.5.30729; .NET4.0C)


    Exception Type: Telerik.Windows.Controls.FileUploadFailedEventArgs


    Message: Handler not found or execution of the handler failed!


    Arguments: NotFound

    Debugging resource strings are unavailable. Often the key and arguments provide sufficient information to diagnose the problem. See http://go.microsoft.com/fwlink/?linkid=106663&Version=5.1.10411.0&File=System.Windows.dll&Key=HttpWebRequest_WebException_RemoteServer

    Check RadUpload's BufferSize property remarks. Error was handled by the application with message box.  File name: Document 134464908.pdf File size: 151733

    Please let me know if there is any other information that might be useful.


  4. Tina Stancheva
    Tina Stancheva avatar
    3299 posts

    Posted 27 Jun 2012 Link to this post

    Hi Ryan,

    This exception is usually raised when the control can't reach the specified UploadHandler and the upload session cannot complete. However, in your case I'm not sure why some attempts to reach the handler as successful while others aren't. Can you try deploying the application in a different server as we feel that the settings of a Windows Server 2008 R2 may be the cause for the issue.

    If this isn't an option for you, you can change the definition of the RadUpload control to specify an absolute path to the RadUploadHandler (setting an absolute path as the value of the UploadServiceUrl property).

    However, if both of these suggestions don't work for you, you can reattempt the upload by implementing a logic for clearing the session and restarting it when the upload fails, like this:
    private void RadUpload1_FileUploadFailed(object sender, FileUploadFailedEventArgs e)
        RadUpload upload = sender as RadUpload;
        List<RadUploadSelectedFile> SelectedFiles = new List<RadUploadSelectedFile>();
        foreach (RadUploadSelectedFile file in upload.CurrentSession.SelectedFiles)
        foreach (RadUploadSelectedFile file in SelectedFiles)

    I hope these suggestions will help you get over the issue. Please let us know how it goes.

    Tina Stancheva
    the Telerik team

    Explore the entire Telerik portfolio by downloading the Ultimate Collection trial package. Get it now >>

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