To reproduce: Add a TableLayout and in the cells add a RadtextBox with its multiline property set to true. Resize the form until the textboxes and unclickable and no scrollbars are shown. This behavior does not always occur.

Workaround: Use a custom RadTextBox class: public class MyTextBox : RadTextBox { protected override void InitializeTextElement() { this.GetType().BaseType.GetField("textBoxElement", BindingFlags.Instance | BindingFlags.NonPublic).SetValue(this, new MyTextBoxElement()); this.TextBoxElement.StretchVertically = true; this.TextBoxElement.ShowBorder = true; } } public class MyTextBoxElement : RadTextBoxElement { protected override SizeF MeasureOverride(SizeF availableSize) { availableSize.Width -= BorderThickness.Size.Width; availableSize.Height -= BorderThickness.Size.Height; SizeF desiredSize = this.MeasureChildren(availableSize); return desiredSize; } protected override Type ThemeEffectiveType { get { return typeof(RadTextBoxElement); } } }