Returning CollectionBase from WebService

[Web Team]

Hi All,

I'm trying to build a webservice that returns a CollectionBase.

I am getting this error:

"You must implement a default accessor on
System.Collecti ons.CollectionB ase because it inherits from
ICollection."

I've searched and searched on this one - Plenty of articles, none of
which make much sense to me, the common thread seems to be that I need
to add some default properties. (I'm new to .Net - Help!)

I've pasted in my code below.

Many Thanks,

Simon.
<WebMethod()> _
Public Function GetAddresses(By Val UPRN As String, ByVal USRN As
Integer, ByVal PostCode As String, ByVal PAON As String, ByVal SAON As
String, ByVal DesignatedStree tName As String, ByVal Easting As Integer,
ByVal northing As Integer) As CollectionBase
Dim AddressCollecti on As New OldInfra.BS7666 .AddressCollect ion
Dim CollAddress As CollectionBase =
AddressCollecti on.GetAddresses (UPRN, USRN, PostCode, PAON, SAON,
DesignatedStree tName, Easting, northing)
Return CollAddress
End Function

[Web Team]

I've added the following code to both my webservice and
AddressCollecti on class. Hasnt made any difference :(

Public Property address() As Address
Get
Return address
End Get
Set(ByVal Value As Address)
address = Value
End Set
End Property