Visual Studio 2010 (64-bit) ORA-06413 error

I've got a vb.net web application that connects to the Oracle DB on my old PC (32-bit, XP Prof.), but now won't on my new PC (64-bit, Windows 7).  All I get is an ORA-06413 "not connected" error

Visual Studio 2010 installed in C:\Program FilesX86\
 - so this should avoid the whole parentheses/Oracle path issue

64-bit Oracle DAC asp.net 4 installed in C:\Oracle64

I can connect in Visual Studio using the Server Explorer ... MSDAORA.ServerName

Here is part of my code:
>>>>
Imports System.Data.OracleClient
Imports System.Data.OleDb

'64-bit - I think -
Dim myConnection As New OleDb.OleDbConnection("Provider=OraOLEDB.Oracle.1;Data Source=XXXX;User ID=XXXX;Password=XXXX;")

Dim myCommand As OleDbCommand
Dim dr As OleDbDataReader

            Try
                myConnection.Open()
                myCommand = New OleDbCommand(QRY5, myConnection)

                dr = myCommand.ExecuteReader()

                ....read into some variables....

            Catch ex As Exception
                ex.Message.ToString()
                Throw

            Finally
                dr.Close()
                myConnection.Close()
>>>>

On the 32-bit PC, this works:
            ' 32 bit
            'Dim myConnection As New OleDb.OleDbConnection("Provider=MSDAORA.1;Data Source=XXXX;User ID=XXXX;Password=XXXX;")

TIA