With Microsoft Office Communications Server 2007 R2 Web Service Provider, administrators can implement basic instant messaging and presence functionality for Microsoft Office Outlook®-Live users. Prior to the Web Service Provider release, Outlook-Live users accessed this functionality through client applications such as Microsoft Office Communicator 2007 or Microsoft Office Communicator Web Access (2007 release).
Web Service Provider does not introduce features excluded from Communicator Web Access (2007 R2 release). It simply gives Outlook-Live users an alternative method for accessing basic instant messaging and presence information. For example, senders of an e-mail will now be able to view presence information from within the Outlook-Live application.

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