Share your experience!
I have the same annoying problem
I set my pc to download from the server.. This 'should' leave no emails 'waiting' for the phone. Yet I ften have the little number over the email icon (its saying there are 6 at the moment) but none are there when i tap the icon and go into my email.
I don't know what to do about it either... i'll keep an eye out on this thread
Never had this on my previous Sony phone.. infact emails would disappear of the phone as the pc downloaded and deleted them off the server.
annoying 
This seems to have been fixed now...
I made a note of the setting in the email accounts i have on the SPO and then deleted both of them
I made new accounts and the problem of the icon indicating I have mail is not there anymore unless there really is mail to view.
Might help someone
Still working ok after a week.
so deleting the account and making a new one has fixed it. 