DirectCast - Object not set to an instance of an object???

[flycast]

I am trying to deserialize a custom object that has been previously serialized and saved in a file. and I have the following code:

        If open.ShowDialog = Windows.Forms.DialogResult.OK Then
            Dim fs As FileStream = New FileStream(open.FileName, FileMode.Open)
            Try
                testing = New ItemInfo
                Dim formatter As New BinaryFormatter
                Dim obj As Object = formatter.Deserialize(fs)
                testing = DirectCast(obj, ItemInfo)
            Catch ex As Exception
                MsgBox(ex.Message)
            Finally
                fs.Close()
            End Try
        End If 

The problem is the line

testing = DirectCast(obj, ItemInfo) 

I am getting an exception:

Object not set to an instance of an object

I have verified that the variable testing and obj are actually instantiated. That leaves ItemInfo which is the name of my custom type (Not an instance of the class).

Since the variable testing and obj are instantiated it seems like it does not like the reference to the class ItemInfo.
What could I be doing wrong here?