GFI MailEssentials 2014 SR2 fully supports Microsoft Exchange 2013 SP1. However the official patch from Microsoft is required to be installed after Exchange Service Pack 1 and prior installing GFI MailEssentials.
If the above patch is not installed then GFI MailEssentials will fail to register the Agents required for scanning emails passing through Exchange server. Customers upgrading to Microsoft Exchange 2013 SP1 are advised to run \GFI\MailEssentials\e2k7wiz.exe to register the Exchange Agents.
This incompatibility is due to some breaking changes introduced by Microsoft in Exchange 2013 SP1 – it does not affect any other version of Exchange.
*** Update: as the original Exchange 2013 SP1 issue has been fixed in the new Exchange 2013 CU5 update, we recommend updating to Exchange 2013 CU5 instead of installing the above mentioned patch.