Using the EmailMessage.Normalize method in a transport agent causes issues with Exchange Server 2013 CU7
I received a report that if you have an existing transport agent and use the method Microsoft.Exchange.Data.Transport.Email.EmailMessage.Normalize(), the transport agent won't work correctly on Exchange Server 2013 CU7. This is because of a known issue where the public signature of this method was changed and so existing transport agents will need to be recompiled to work with Exchange Server 2013 CU7. This issue will be addressed in a future update to the product. In the meantime, you should recompile using the new method signature and maintain that code base until the update containing the fix is released publicly.
EmailMessage.Normalize method