I have a problem in my OPC client application using `OPC NET API 2.00`, so when I want to connect to ABB Freelance OPC Server, it throws an exception when calling `Opc.Server.Connect(Opc.ConnectData)` method.

Exception:

> 
> Unable to cast COM object of type 'System.\_\_ComObject' to
>  interface type 'OpcRcw.Comn.IOPCServerList2'. This operation failed
>  because the QueryInterface call on the COM component for the interface
>  with IID '{9DD0B56C-AD9E-43EE-8305-487F3188BF7A}' failed due to the
>  following error: No such interface supported (Exception from HRESULT:
>  0x80004002 (E\_NOINTERFACE)).
> 
> 
> 

May be Problem relates to `IOPCServerList2` interface:

```
#region Assembly OpcRcw.Comn.dll, v1.10.2.0
// C:\Windows\assembly\GAC_MSIL\OpcRcw.Comn\1.10.2.0__9a40e993cbface53\OpcRcw.Comn.dll
#endregion

using System;
using System.Runtime.InteropServices;

namespace OpcRcw.Comn
{
    [Guid("9DD0B56C-AD9E-43EE-8305-487F3188BF7A")]
    [InterfaceType(1)]
    public interface IOPCServerList2
    {
        void CLSIDFromProgID(string szProgId, out Guid clsid);
        void EnumClassesOfCategories(int cImplemented, Guid[] rgcatidImpl, int cRequired, Guid[] rgcatidReq, out IOPCEnumGUID ppenumClsid);
        void GetClassDetails(ref Guid clsid, out string ppszProgID, out string ppszUserType, out string ppszVerIndProgID);
    }
}

```