C#

listview1.Groups[0].Items.Add("item");

System.Runtime.Serialization.SerializationException was unhandled
  Message="Unable to find assembly 'SmallTalkServer, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null'."
  Source="mscorlib"

bf.AssemblyFormat = FormatterAssemblyStyle.Simple;

using System.IO;
using System.Runtime.Serialization;
using System.Runtime.Serialization.Formatters.Binary;
using System.Runtime.Serialization.Formatters;


namespace SmallTalkServer
{
    public static class Serializer
    {

        public static void SerializeObject(string filename, BuddyList buddyList)
        {
            Stream stream = File.Open(filename, FileMode.Create);
            BinaryFormatter bFormatter = new BinaryFormatter();
            bFormatter.AssemblyFormat = FormatterAssemblyStyle.Simple;
            bFormatter.Serialize(stream, buddyList);
            stream.Close();
        }

        public static BuddyList DeSerializeObject(string filename)
        {
            BuddyList buddylist;
            Stream stream = File.Open(filename, FileMode.Open);
            BinaryFormatter bFormatter = new BinaryFormatter();
            bFormatter.AssemblyFormat = FormatterAssemblyStyle.Simple;
            buddylist = (BuddyList)bFormatter.Deserialize(stream);
            stream.Close();
            return buddylist;

        }
        public static BuddyList DeSerializeObject(byte[] arrBytes)
        {
            MemoryStream memStream = new MemoryStream();
            memStream.Write(arrBytes, 0, arrBytes.Length);
            memStream.Seek(0, SeekOrigin.Begin);
            BuddyList buddylist;
            BinaryFormatter bFormatter = new BinaryFormatter();
            bFormatter.AssemblyFormat = FormatterAssemblyStyle.Simple;
            buddylist = (BuddyList)bFormatter.Deserialize(memStream);
            memStream.Close();
            return buddylist;

        }

        public static byte[] ObjectToByteArray(object obj)
        {
            if (obj == null)
                return null;
            BinaryFormatter bf = new BinaryFormatter();
            bf.AssemblyFormat = FormatterAssemblyStyle.Simple;
            MemoryStream ms = new MemoryStream();
            bf.Serialize(ms, obj);
            return ms.ToArray();

        }

        public static object ByteArrayToObject(byte[] arrBytes)
        {
            MemoryStream memStream = new MemoryStream();
            BinaryFormatter binForm = new BinaryFormatter();
            binForm.AssemblyFormat = FormatterAssemblyStyle.Simple;
            memStream.Write(arrBytes, 0, arrBytes.Length);
            memStream.Seek(0, SeekOrigin.Begin);
            object obj = (object)binForm.Deserialize(memStream);
            return obj;
        }
    }
}