C# OPC Client fails to get server list

C# OPC Client fails to get server list

After I compiled my C# in my new Windows 8 64-Bit machine, I started to
get the following error while getting list of available servers in my OPC
client application.
"OpcNetApi.Com 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: Class not registered (Exception from HRESULT: 0x80040154
(REGDB_E_CLASSNOTREG))."
What could be the reason?