Event handlers not registering

 private void Disconnect()
   {
     textBox1.Invoke(changeStateTextBoxDisconnect);
     button1.Invoke(changeStateButton1Disconnect);
     button2.Invoke(changeStateButton2Disconnect);
     button3.Invoke(changeStateButton3Disconnect);
   }

  private void changeStateButton1Disconnect()
  {
    button1.Text = "Ingresar";
    button1.MouseClick -= Disconnect;
    button1.MouseClick += ConnectionRequest;
  }

   private void ConnectionRequest(object sender, MouseEventArgs e)
   {
     if (textBox1.Text.Equals(string.Empty))
     {
       MessageBox.Show("Ingrese una identificacion");
       return;
     }
     _childThread = new Thread(new ParameterizedThreadStart(StartConnection)) { IsBackground = true };
     _childThread.Start(this.textBox1.Text);
     _connected = true;
     if (_connected)
     {
       button1.MouseClick -= ConnectionRequest;
       button1.MouseClick += Disconnect;
       textBox1.Enabled = false;
       button1.Text = "Desconectar";
       button2.Enabled = true;
       button3.Enabled = true;
     }
   }