title: Is it possible to programmatically password protect an excel spreadsheet?
body: <p>We currently create Excel spreadsheets on our server which are then mailed to customers. We now need to password protect these files. Is it possible to programmatically add Excel password protection to these files? </p>
  
  <p>I would prefer not to install Excel on the server and use a form automation to do this.</p>
  
  <p>I am a C#/.net developer, but any language/method to do this would be appreciated</p>