I'm trying to compile myGeneration PropertyCollectionAll.cs  file with VCS
Express 2005 bot got error

Error 1 The type or namespace name 'Collection' could not be found (are you
missing a using directive or an assembly reference?)
PropertyCollectionAll.cs 17 39

I looked to .NET 2 help and found that Collection class is included in
mscorlib so it doen't need assembly reference.
How to fix this error ?

Whole file which causes this error is:

using System;
using System.Xml;
using System.Collections;
using System.Data;
using System.Data.OleDb;

namespace MyMeta
{

public class PropertyCollectionAll : Collection, IPropertyCollection,
IEnumerable, IEnumerator, ICollection
{

 public PropertyCollectionAll()
 {

 }

 internal void Load(IPropertyCollection local, IPropertyCollection global)
 {
  this._local  = local;
  this._global = global;
 }

 #region IPropertyCollection
   //[System.Runtime.InteropServices.DispId(0)]
 public IProperty this[string key]
 {
  get
  {
   if(this._local.ContainsKey(key))
   {
    return this._local[key];
   }
   else if(this._global.ContainsKey(key))
   {
    return this._global[key];
   }

   return null;
  }
 }

 /// <summary>
 /// This method will either add or update a key value pair.  If the key
already exists in the collection the value will be updated.
 /// If this key doesn't exist the key/value pair will be added.  If only
want to update, and not add new items, use <see cref="ContainsKey"/> to
determine if the key already exists.
 /// </summary>
 /// <param name="key"></param>
 /// <param name="value"></param>
 /// <returns></returns>
 public IProperty AddKeyValue(string key, string value)
 {
  throw new NotImplementedException("Cannot call AddKeyValue on this
collection");
 }

 /// <summary>
 /// Removes a key/value pair from the collection, no error is thrown if
the key doesn't exist.
 /// </summary>
 /// <param name="key">The key of the desired key/value pair</param>
 public void RemoveKey(string key)
 {
  throw new NotImplementedException("Cannot call AddKeyValue on this
collection");
 }

 /// <summary>
 /// Use ContainsKey to determine if a key exists in the collection.
 /// </summary>
 /// <param name="key">The key of the desired key/value pair</param>
 /// <returns>True if the key exists, False if not</returns>
 public bool ContainsKey(string key)
 {
  if(this._local.ContainsKey(key))
  {
   return true;
  }
  else if(this._global.ContainsKey(key))
  {
   return true;
  }

  return false;
 }

 /// <summary>
 /// Removes all key/value pairs from the collection.
 /// </summary>
 new public void Clear()
 {
  throw new NotImplementedException("Cannot call AddKeyValue on this
collection");
 }
 #endregion

 #region IEnumerable Members

 public IEnumerator GetEnumerator()
 {
  Reset();
  return (this as IEnumerator);
 }

 #endregion

 #region IEnumerator Members

 public void Reset()
 {
  useLocalEnum = true;
  wereDone = false;
  _localEnumerator  = this._local.GetEnumerator();
  _globalEnumerator = this._global.GetEnumerator();
 }

 public object Current
 {
  get
  {
   IProperty prop = null;

   if(useLocalEnum)
   {
    prop = (IProperty)_localEnumerator.Current;
   }
   else
   {
    prop = (IProperty)_globalEnumerator.Current;
   }

   return prop;
  }
 }

 public bool MoveNext()
 {
  if(this.useLocalEnum)
  {
   if(_localEnumerator.MoveNext()) return true;
  }

  if(!wereDone)
  {
   this.useLocalEnum = false;

   while(true)
   {
    if(_globalEnumerator.MoveNext())
    {
     IProperty prop = (IProperty)_globalEnumerator.Current;

     if(!this._local.ContainsKey(prop.Key))
     {
      return true;
     }
    }
    else
    {
     break;
    }
   }

   wereDone = true;
  }

  return false;
 }

 #endregion

 #region ICollection Members

 public new  bool IsSynchronized
 {
  get
  {
   // TODO:  Add Databases.IsSynchronized getter implementation
   return false;
  }
 }

 public new void CopyTo(Array array, int index)
 {
  // TODO:  Add Databases.CopyTo implementation
 }

 public new object SyncRoot
 {
  get
  {
   // TODO:  Add Databases.SyncRoot getter implementation
   return null;
  }
 }

 #endregion

 private IPropertyCollection _local;
 private IPropertyCollection _global;

 bool useLocalEnum = true;
 bool wereDone = false;
 private IEnumerator _localEnumerator = null;
 private IEnumerator _globalEnumerator = null;
}
}