Some of the highlight of SP1.
Windows Server 2012 R2 Support First answering one the most common questions since the release of Windows Server 2012 R2. Exchange 2013 SP1 will add Windows Server 2012 R2 as a supported operating system for Exchange Server 2013 with SP1. Let your planning begin.
S/MIME support for OWA Support for S/MIME in OWA will be brought back in SP1. With SP1 customers will have S/MIME support across Outlook, Exchange ActiveSync clients, and OWA.
Edge Transport Server Role The Edge Transport server role for Exchange Server 2013 will be available with SP1.
Fixes and Improvements Of course, SP1 will include fixes and improvements in areas you’ve helped us identity. SP1 is the first service pack issued in the new Exchange Server cumulative update release model – thus SP1 is essentially CU4. The installation of SP1 will follow the same process as the prior Exchange 2013 CU releases. SP1 will include all fixes included in previously released cumulative updates for Exchange 2013.