title: USB Debugging option greyed out
body: <p>I have an LG-E405 phone running Android 2.3.6.</p>
  
  <p>I connected my phone with a USB cable and selected the mode as <code>Charge Only</code>.</p>
  
  <p>Now when I try to turn on <code>USB Debugging</code>, I find that that the option is greyed out.</p>
  
  <p>So, how can I enable USB debugging in this case.</p>