An application must have special permission to use advanced features outside of the standard, controlled set of methods and properties. These permissions can be granted in the form of permission flags that are set in the application's entry in the Windows Live Messenger Activity Directory. When an author submits an application for inclusion in the Activity Directory, the author can request that permission flags be set to accommodate the demands of the application. Before an application with special permissions appears in the Activities directory, it must be reviewed by Microsoft. There is no guarantee that a review will take place within a particular time frame, or that the requested permissions will be granted.

The following list describes available permission flags and the advanced features to which they grant access:

• Permission Flags - ActiveX—Required to host ActiveX controls on the application Web page.
  
• Permission Flags - EnableIP—Required to get the IP addresses for the computers running the application.
  
• Permission Flags - PassportSiteID—Required to perform Microsoft .NET Passport authentication, or to get the user name or e-mail address of a participant.
  
• Permission Flags - ReceiveIM—Required to view the contents of incoming chat messages.
  
• Permission Flags - ReplaceIM—Required to intercept and replace the contents of incoming chat messages.
  
• Permission Flags - SendFile—Required to send files as part of the application.
  
• Permission Flags - SendIM—Required to send a chat message to the remote user, either as the local user or as the application.
  
• Permission Flags - UserProperties—Required to perform Microsoft .NET Passport authentication, or to get the user name or e-mail address of a participant, without performing authentication when the application loads.