I have the 1020 with ATT. I use three email accounts, gmail, outlook, and Comcast imap. My Comcast account periodically deletes all emails. I have no idea why. I've checked all settings both on the phone and with Comcast and cannot figure out why this happens. It has nothing to do with the age of the messages. It deletes old and new messages. I believe it is a Win 8 issue because I see the same problem on my Surface RT and Pro. I have not had this problem on non-Win 8 devices.