Another User or Device is Deleting Mail

Problem: Emails seem to be deleting themselves after a certain number of days. Cause: You are most likely sharing your email with someone else in the company or you have the account set up on other devices. The email account on one of those other computers/devices were set up as a POP account and the account was set to delete from the server after X amount of days.… Read more of this article

Your Email Account has possibly been hacked

I know this sounds scary and technically it’s not a good thing, however it is repairable. Things that confirm your email has been hacked: You’re receiving a large number of bounced emails (emails that are coming from other servers that are saying the email has been sent to an account that does not exist and they’ve provided something like… Read more of this article

The Device is Not Sharing Mail

The problem explained a little more: The emails are most likely not reaching both or all of your devices. There are two types of accounts: POP and IMAP.  Depending on which you have, the problem and solution is different. You can determine which one you have by looking at the settings in your device for that particular email account. You should be able to see a label… Read more of this article