Hi, I have an 2011/2012 18month old iMac (not sure of model) and have been using the apple email that was originally installed on computer. Today it would not retrieve emails and whilst fiddling around I pressed "rebuild". All my inbox emails, around 600, now read (no sender) (no subject)with nothing in them. All my sent emails and trash are still there and are readable. Is there anyway to restore these emails. Some of them are crucial. Any help would be greatly appreciated.