Microsoft WebDAV Extension for IIS 7.0 (x86) : Download : Microsoft Internet Information Services
Microsoft has created a new WebDAV extension module that has been completely rewritten for Windows Server 2008. This new WebDAV extension module incorporates many new features that enable web authors to publish content better than before, and offers web administrators more security and deployment options. For additional information, please see our documentation.
This new WebDAV extension module is only for Windows Server 2008 and Internet Information Services 7.0; it will not work on Windows Server 2003 and Internet Information Services 6.0.
Link: IIS.net : Microsoft WebDAV Extension for IIS 7.0 (x86) : Download : Microsoft Internet Information Services