My website clients also get email addresses tossed in for free. So if the client’s company is “Acme” and their site address is “acme.com” then I can sign them up with emaill address like “ceo@acme.com” or “director@acme.com” or “jane@acme.com”.

Unlike the websites which I create and maintain and control for them, I have absolutely no control over their email. The host I use for those sites provides the email servers, and all I can do is assign addresses. In fact, other than the name, the email has no relationship at all to the site. The email is handled entirely by the host, and is not even on the same server as the website. In fact, I happen to know that their email server is literally 2000 miles away from my website server.

They run it; I do not.

How email works is rocket science, and there are  folks who make careers out of running it. It’s complex; subject to privacy laws; and spammers are attacking email system continuously. (In fact, 281.1 billion e-mails were sent and received on a daily basis, and 65% of them are spam.) This is a huge and complex enterprise.

In view of that, you can understand exactly why the people that run such systems not only forbid, but make it darned near  impossible, for anyone but themselves to mess with almost all of the parameters. 

When an email server has problems, 99.9% of the time it affects thousands if not millions of people – not just one iPhone.

Here’s an analogy that is very close to what happens with email.

You get email sent from around the world, and any time, day or night. Because it arrives 24/7, it has to be stored somewhere –  It all goes into a large “bucket” which just sits there collecting emails. Think of a bucket of water: you pour some in, and then some more, but the bucket of water just sits there. Likewise, the email bucket just sits there passively collecting emails.

Nothing happens to the water while it’s in the bucket. Nothing. BUT, if YOU grab a cup and dip into the bucket, you get back some water. Well, that “cup” is your email client on your iPhone, computer, laptop or whatever. 

When you check your email (dip in with your cup), the server/bucket sends you a list of what is IN the bucket. The bucket itself does NOT send you anything but the list; you go grab it. You click on something on that list, and a copy of it is displayed for you by your client. Unless you specifically delete the email, it is still sitting there in the bucket, ready  to send you another copy, or be read by another of your devices, like your laptop; iPhone; desktop and so on.

So, your email client is the cup. It is what grabs a copy of the mail in your bucket.

The client does the work. You can save a copy of the email to your local hard drive; you can delete an email from the bucket; you can forward the email to someone, or you can reply.

So, if you have problems getting email on one device, but not on another, then the problem is with the one device. It is not, and cannot be, a problem with the bucket, because if there were some problem on the bucket,  then ALL your devices would fail, not just one.

If you are in the circumstance that you get email on your iPhone, but not on your laptop, the something has changed on your laptop. The bucket  is still just sitting there.

Here’s what happens: the email remains in your INbox, which is the IMAP server, the bucket , until you delete it. So, that way, you can read the email on your laptop, your desktop and your iPhone. However, if your delete it on any of those devices, you have deleted it from the server. Obviously, since it’s now gone, you cannot read it on any other device.

To keep a backup (and you should!) simply make a new mailbox in your client, and drag the message into it. Now you can delete it from your INbox because you have a copy in a different mailbox.