C# System.NullReferenceObject while reading XML

A System.NullReferenceObject exception is cast when I try to read the following XML:

<Settings>
  <Shortcuts>
    <Shortcut_1>CTRL+ALT+1</Shortcut_1>
    <Shortcut_2>CTRL+ALT+2</Shortcut_2>
    <Shortcut_3>CTRL+ALT+3</Shortcut_3>
    <Shortcut_4>CTRL+ALT+4</Shortcut_4>
    <Shortcut_5>CTRL+ALT+5</Shortcut_5>
    <Shortcut_6>CTRL+ALT+6</Shortcut_6>
    <Shortcut_7>CTRL+ALT+7</Shortcut_7>
    <Shortcut_8>CTRL+ALT+8</Shortcut_8>
    <Shortcut_9>CTRL+ALT+9</Shortcut_9>
    <Shortcut_10>CTRL+ALT+10</Shortcut_10>
  </Shortcuts>
  <Other>
    <Windows_start>true</Windows_start>
    <Report_bugs>false</Report_bugs>
  </Other>
</Settings>

Using the following code:

public static string Read(string read)
    {
        try
        {
            XmlDocument doc = new XmlDocument();
            doc.Load(AppDomain.CurrentDomain.BaseDirectory + "Settings.xml");

            XmlNode node = doc.DocumentElement.SelectSingleNode(read);
            //The line below causes the error.
            string contents = node.InnerText;

            return contents;
        }
        catch (Exception ex)
        {
            MessageBox.Show(ex.ToString(), "Error!", MessageBoxButtons.OK, MessageBoxIcon.Error);

            return "";
        }
    }

My intent is to read the Windows_start tag and the Report_bugs tag from the XML file using the above method.