XML Deserializer throwing Exception

HexTester.cs

using System;
using System.Collections.Generic;
using System.IO;
using System.Text;
using System.Xml.Serialization;

namespace XMLTester
{
    public class HexTester
    {
        public static void Main(string[] args)
        {

            var lines = File.ReadAllLines(@"..\..\HexText.txt"); ;

            var foo = new Foo()
            {
                Items = new List<FooBar>()
                    {
                        new FooBar()
                        {                            
                            Text = lines[0]                        
                        }
                    }
            };

            string xml = SerializeToXML(foo);
            var objTabs = DeserializeFromXML(xml, typeof(Foo));
        }

        static string SerializeToXML(object obj)
        {
            StringBuilder xml = new StringBuilder();
            XmlSerializer serializer = new XmlSerializer(obj.GetType());
            TextWriter textWriter = new StringWriter(xml);
            serializer.Serialize(textWriter, obj);
            textWriter.Close();

            return xml.ToString();
        }

        static object DeserializeFromXML(string xml, Type toType)
        {
            XmlSerializer deserializer = new XmlSerializer(toType);
            TextReader textReader = new StringReader(xml);

            Object obj = deserializer.Deserialize(textReader);
            textReader.Close();

            return obj;
        }

    }

    public class Foo
    {
        public List<FooBar> Items { get; set; }
    }
    public class FooBar
    {
        public string Text { get; set; }
    }
}