Controls in RadPanel redraw slowly when changing the Enabled state of the panel. Workaround: private void radButton1_Click(object sender, EventArgs e) { if (this.radPanel1.Enabled) { this.radPanel1.Enabled = false; } else { this.radPanel1.Visible = false; this.radPanel1.Enabled = true; this.radPanel1.Visible = true; } }