I'm running into a major issue with the built in HTML editor in DNN 9.2.1 as I cannot access the editor manager from the Persona Bar. Instead I am greeted by this error message.

"Object reference not set to an instance of an object."

The Admin Log shows a Page Load Exception with this detail.

Any ideas as to what is going wrong and how to fix it. It was working fine in 9.2.0.

InnerStackTrace:

   at DNNConnect.CKEditorProvider.CKEditorOptions.BindUserGroupsGridView()
   at DNNConnect.CKEditorProvider.CKEditorOptions.Page_Load(Object sender, EventArgs e)
   at System.Web.UI.Control.OnLoad(EventArgs e)
   at DotNetNuke.Entities.Modules.PortalModuleBase.OnLoad(EventArgs e)
   at System.Web.UI.Control.LoadRecursive()
   at System.Web.UI.Control.LoadRecursive()
   at System.Web.UI.Control.LoadRecursive()
   at System.Web.UI.Control.LoadRecursive()
   at System.Web.UI.Control.LoadRecursive()
   at System.Web.UI.Control.LoadRecursive()
   at System.Web.UI.Control.LoadRecursive()
   at System.Web.UI.Control.LoadRecursive()
   at System.Web.UI.Control.LoadRecursive()
   at System.Web.UI.Control.LoadRecursive()
   at System.Web.UI.Control.LoadRecursive()
   at System.Web.UI.Control.LoadRecursive()
   at System.Web.UI.Control.LoadRecursive()
   at System.Web.UI.Control.LoadRecursive()
   at System.Web.UI.Control.LoadRecursive()
   at System.Web.UI.Control.LoadRecursive()
   at System.Web.UI.Control.LoadRecursive()
   at System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint)

Any ideas as to what is going wrong and how to fix it. It was working fine in 9.2.0.