There are three devices that my email is downloaded to - my office desktop, my Surface, and my LG4 phone. That doesn't seem to complicated (at first). But, I have yet to figure out the synchronization and configuration pattern and I am stuck three different places that store my sent mail (only the phone keeps it on the server). Of course, I have complicated this by having 5 personal email addresses, and 3 business email addresses that are spread across three different providers/servers.
The primary and most used email is obviously firstname.lastname@example.org. I established this email with this provider long ago figuring that yahoo would never go out of the email business. However there have been times when a yahoo is down or acting up which require that I send email through gmail. Of course that confuses many people as to which email to use (because so many people don't know how Outlook establishes contacts and/or preferences on reply or new emails).
Today, I spent the better part of the day configuring Outlook 2007 (on my desktop) to consolidate all emails into one inbox (Cincinnati Bell had suspended various emails for added security features). This required new account configurations in Outlook (and naturally I have various versions of Outlook).
The challenge becomes all the account settings with IMAP or POP3, Ports to use, SSL,TSL etc. Then you must establish standards which device deletes emails from server or to keep them forever until deleted when signed on to the server.
I still haven't researched my subscription to Outlook365 for my HP Stream7 which is Windows 10 and Outlook 2016 (although I have figured out how to put my Surface Outlook pst file on a mini SD Memory card for easy transport).
Most conservatives want to crucify Hilary Clinton for her email security snafu and maybe they are correct because of the sensitive security needs of her position. However, I can relate to the greater part of our population that have NO CLUE on email infrastructure - including me!
Next project - Synchronized Calendars