Cannot add RadCheckBox. Error is saying 'Telerik.WinControls.UI' already exists in the project?

4 posts, 1 answers
  1. Heath
    Heath avatar
    6 posts
    Member since:
    Oct 2014

    Posted 12 Nov 2014 Link to this post

    I am servicing an application I did not write. It was written using Telerik UI for Winforms.  I was asked to add a new checkbox. Easy enough, or so I thought. I went to the toolbox and dragged the radcheckbox from telerik UI over to my form and got an error message.I have attached the entire error. The error is telling me that 'Telerik.WinControls.UI' already exists in the project.

    My dev environment is straight forward enough. The application seems to have been written in .NET Framework 4 and I am using Visual Studios 2013. Anybody encounter this problem? What could be the fix?
  2. Answer
    Stefan avatar
    2911 posts

    Posted 13 Nov 2014 Link to this post

    Hello Heath,

    Thank you for writing.

    Please refer to the following article where you can find the answer to your question:

    I hope that you find this information useful. Should you have any other questions, do not hesitate to contact us.


    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.

  3. Hannah
    Hannah avatar
    37 posts
    Member since:
    May 2013

    Posted 16 Jun 2016 Link to this post

    Would love it if people would put answers in the body of their response rather than linking....that link is dead and this is no help to anyone now.
  4. Dess | Tech Support Engineer, Sr.
    Dess | Tech Support Engineer, Sr.  avatar
    3758 posts

    Posted 17 Jun 2016 Link to this post

    Hello Wayne,

    Thank you for writing. 

    Please refer to the up to date link:

    I hope this information helps. Should you have further questions I would be glad to help.

    Check out the Windows Forms project converter, which aids the conversion process from standard Windows Forms applications written in C# or VB to Telerik UI for WinForms.For more information check out this blog post and share your thoughts.
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