S/MIME support for Exchange Active Sync (EAS) version 2.5 was introduced in Exchange 2003 Service Pack 2 (SP2) and Windows Mobile 5 (WM5) device. In Exchange 2007 SP1, we are adding S/MIME support for EAS version 2.5, 12.0 and 12.1. While working on EAS S/MIME implementation, I was asked how users could enable their devices work with S/MIME. Below I have provided some simple end-to-end steps to exemplify using S/MIME on a Windows Mobile device.
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