You need to download Microsoft ActiveSync in case using Windows XP from: http://www.microsoft.com/windowsmobile/en-us/help/synchronize/activesync-download.mspx
and in case of windows VISTA, download Windows Mobile Device Center from: http://www.microsoft.com/windowsmobile/en-us/downloads/microsoft/device-center-download.mspx
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You need to download Microsoft ActiveSync in case using Windows XP from:
http://www.microsoft.com/windowsmobile/en-us/help/synchronize/activesync-download.mspx
and in case of windows VISTA, download Windows Mobile Device Center from:
http://www.microsoft.com/windowsmobile/en-us/downloads/microsoft/device-center-download.mspx