unknown server tag errors after upgrading web application

4 posts, 0 answers
  1. Randy
    Randy avatar
    26 posts
    Member since:
    Jul 2013

    Posted 21 Nov 2016 Link to this post

    I have a Visual Studio 2015 web project that uses RadScheduler and RadEditor.

    I just downloaded the latest Telerik version (2016.3.1027) and updated the project.

    Now when I build the solution, I get the following errors:

    Unknown server tag 'dc:TableDesign'.....file: TableWizard.ascx.....Line: 844

    Unknown server tag 'Telerik:TableBorder'.....file: TableProperties.ascx.....Line: 362



  2. Marin Bratanov
    Marin Bratanov avatar
    5254 posts

    Posted 22 Nov 2016 Link to this post

    Hi Randy,

    I advise that you perform a manual upgrade: http://docs.telerik.com/devtools/aspnet-ajax/installation/upgrading-instructions/upgrading-a-trial-to-a-developer-license-or-to-a-newer-version#manual-upgrade.

    If you have customized the editor dialogs, I advise that you take the new ones from the installation of the new version and apply your changes on them.


    Marin Bratanov
    Telerik by Progress
    Telerik UI for ASP.NET AJAX is ready for Visual Studio 2017 RC! Learn more.
  3. Polymorphic Solutions
    Polymorphic Solutions avatar
    4 posts
    Member since:
    Sep 2009

    Posted 21 Jan Link to this post


    I know this is an old post. But I am also having the same issue from our end. We are currently using version 2017.1.118.40.

    Can I please request for assistance?

    Thank you.


  4. Rumen
    Rumen avatar
    14285 posts

    Posted 21 Jan Link to this post

    Hi there,

    If RadEditor in your app is configured to use external dialogs (e.g. the ExternalDialogsPath Property is set) please make sure that the files in the EditorDialogs folder are up to date and obtained from the same installation as the Telerik.Web.UI.dll assembly.

    You can also put 

                    <add tagPrefix="telerik" namespace="Telerik.Web.UI" assembly="Telerik.Web.UI" />

    in the web.config file.

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