I had a profile installed on my iphone and was able to read encrypted emails from my list of senders that habitually encrypt. My cert expired, so I created a new one. I deleted the old profile, installed a new one from my .p12 (exported from Keychain on my mac once the new cert was installed there), and thought that I would be good to go. Unfortunately, that's not the case - I can't decrypt anybody else's email, or sign/encrypt my own messages. I see the profile in General-> Profile, it's trusted. I see my cert in the Account->Advanced->Sign section, it's trusted. I can read encrypted mail sent to myself from my laptop, where all of this works fine. What the heck? Any ideas on how to troubleshoot?