`method_missing': unknown property or method: 'Application' (WIN32OLERuntimeError) using Ruby 187 with Win 7

Using Ruby 1.8.7 on a Windows 7 machine with Office 2010.

Initiated use of Excel api with  ..  require 'win32ole'   ..  self.excel = WIN32OLE::new("Excel.Application")

code works thru this point.

Failure on any subsequent Excel methods like  ..  self.excel.Visible = false  or  self.excel.Application.DisplayAlerts = false.

Identical code worked on an XP machine with Office 2003.

Please advise.