To reproduce: - Add some comments and try to navigate through them. - Try add or show/hide the comments while the cursor is in one of the comments. Workaround: Create a custom RichTextEditorRibbonBar and override the following methods: Public Class MyRichTextEditorRibbonBar Inherits RichTextEditorRibbonBar Protected Overrides Sub ButtonNewComment_Click(sender As Object, e As EventArgs) Dim command As New InsertCommentCommand(Me.AssociatedRichTextEditor.RichTextBoxElement) Me.ExecuteCommand(command) End Sub Protected Overrides Sub ButtonDeleteComment_Click(sender As Object, e As EventArgs) Dim command As New DeleteCommentCommand(Me.AssociatedRichTextEditor.RichTextBoxElement) Me.ExecuteCommand(command) End Sub Protected Overrides Sub ButtonPreviousComment_Click(sender As Object, e As EventArgs) Dim command As New GoToPreviousCommentCommand(Me.AssociatedRichTextEditor.RichTextBoxElement) Me.ExecuteCommand(command) End Sub Protected Overrides Sub ButtonNextComment_Click(sender As Object, e As EventArgs) Dim command As New GoToNextCommentCommand(Me.AssociatedRichTextEditor.RichTextBoxElement) Me.ExecuteCommand(command) End Sub Protected Overrides Sub ToggleButtonShowHideComments_ToggleStateChanged(sender As Object, args As StateChangedEventArgs) Dim command As New ToggleCommentsCommand(Me.AssociatedRichTextEditor.RichTextBoxElement) Me.ExecuteCommand(command) End Sub Protected Overrides Sub ButtonDeleteAllComments_Click(sender As Object, e As EventArgs) Dim command As New DeleteAllCommentsCommand(Me.AssociatedRichTextEditor.RichTextBoxElement) Me.ExecuteCommand(command) End Sub Protected Overrides Sub HandleDocumentCommandExecuted(document As RadDocument) MyBase.HandleDocumentCommandExecuted(document) Dim hasComments As Boolean = Me.AssociatedRichTextEditor.Document.EnumerateChildrenOfType(Of CommentRangeStart)().Count() > 0 Me.buttonPreviousComment.Enabled = hasComments Me.buttonNextComment.Enabled = hasComments Me.buttonDeleteComment.Enabled = hasComments Me.buttonDeleteAllComments.Enabled = hasComments End Sub End Class