title: How change excel 2007 document orientation to landscape by OpenXML sdk
body: <p>I need help with changing excel 2007 document orientation to landscape. I have not found any helpful information about this. I am using OpenXML SDK for this.
  The only thing I have found: when I create a new Worksheet I should set PageSetup() { Orientation = OrientationValue.Landscape}; But this doesn't help. 
  Can anybody help with this problem?
  Thank you.</p>