<p>Hi there,</p><p>I need to allow form editors to add simple formatting (bold / italic) to an existing form that displays content in a Textarea currently.</p><p>When I change the form control to HtmlInput the form no longer renders and the following server error is displayed:</p><p><a href="http://dnndev.com/fiddle/fid/591">See code changes in Fiddle here</a></p><p>============================================================</p><p>Server Error in '/' Application.</p><p> <em>Unable to cast object of type 'KnowBetter.XModPro.Web.Controls.Form.CheckboxList' to type 'System.Web.UI.HtmlControls.HtmlInputHidden'.</em> </p><p> <strong> Description: </strong>An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code.</p><p> <strong> Exception Details: </strong>System.InvalidCastException: Unable to cast object of type 'KnowBetter.XModPro.Web.Controls.Form.CheckboxList' to type 'System.Web.UI.HtmlControls.HtmlInputHidden'.<br></p><p> <strong>Source Error:</strong> <br></p> <table> <tbody><tr> <td> <code> An unhandled exception was generated during the execution of the current web request. Information regarding the origin and location of the exception can be identified using the exception stack trace below.</code> </td> </tr> </tbody></table> <br> <strong>Stack Trace:</strong> <br><br> <table> <tbody><tr> <td> <code><pre>[InvalidCastException: Unable to cast object of type 'KnowBetter.XModPro.Web.Controls.Form.CheckboxList' to type 'System.Web.UI.HtmlControls.HtmlInputHidden'.] DotNetNuke.Providers.RadEditorProvider.EditorProvider.Panel_PreRender(Object sender, EventArgs e) +748</pre> </code></td></tr></tbody></table>