Microsoft Exchange Server 2010 includes a feature named WebReady Document Viewing. WebReady Document Viewing lets users view common file types in the Outlook Web App Web browser without having the applications associated with those file types installed on the computer they're using. Users can view the following kinds of files using WebReady Document Viewing:

• .doc
  
  
• .pdf
  
  
• .ppt
  
  
• .xls
  
  
• .docx
  
  
• .xslx
  
  
• .pptx
  
  

Additionally, the supported MIME types are as follows:

• application/pdf
  
  
• application/vnd.ms-excel
  
  
• application/vnd.ms-powerpoint
  
  
• application/word
  
  
• application/x-mspowerpoint
  
  
• application/x-msexcel
  
  

You can control direct file access through Outlook Web App by specifying the types of files that users can access and how the files can be accessed. You do this using the Allow, Block, and Force Save options for direct file access in the Exchange Management Console, or by using the file access parameters available in the Set-OWAVirtualDirectory cmdlet in the Exchange Management Shell. In addition to being able to specify Allow, Block, or Force Save for different file types, you can configure the file access options depending on whether the user clicks This is a public computer or This is a private computer when they sign in to Outlook Web App. For more information about how to manage file access, see Configure Public and Private Computer File Access and Set-OwaVirtualDirectory.