How email works

Here’s a brief explanation of how email works.

When you send an email to a friend, it has an address like user@domain.ext.  The email you’re sending goes to an outgoing mail server (a computer) via Simple Mail Transfer Protocol. The SMTP servertries to figure out where to send it, but It doesn’t understand people’s names or addresses however. “bill@gmail.com” means nothing to it at all. So the SMTP server contacts a Domain Name System server (another computer.) The DNS server is like an old phone book for the internet; it translates names to numbers, to an IP address like “123.456.78.910.” Then the DNS server checks that IP address to see if it can receive email. If so,  …

The DNS Server sends the appropriate “decoded” infomation (the IP address) back to the first SMTP server. Now that it has the proper info, the message gets sent from that server to the target domain’s mail exchange server (yet another computer). This server is called a MTA, or Mail Transfer Agent. the MTA decides exactly where to send the email. The MTA then transfers the email to your friend’s IMAP server (yes: another computer) where it resides on a hard drive until your friend goes and fetches the mail, to their own computer.

If you’re counting, that’s 7 transfers between 6 computers.

And just to make this all the more fun, every time something (such as an email or a web page) is sent over the internet, it is broken into tiny chunks, each with a header (ie destination address) and some chunk of the whole data. There may be only a few, or there may be thousands of these packets. And they do not all take the same route to get to the destination. Some may go almost directly while others may travel around the world. Along the way they have gone thru dozens or hundreds of other computers. Then they are all reassembled at the destination (even though they likely arrived out of order.)

As you can see now, this IS “rocket science” and FAR more complex than you might have thought.

And that’s the way every single one of the 300 Billion emails sent each day works.

Nobody tracks all this as it is sent either. There are tens of TRILLIONS of packets flitting around the internet every day. Even computers cannot track all that.

What does happen, however, is that the path taken is added to the hidden header inside each email. You probably didn’t know it was there, but it is. If you get an email, and your email software offers it, there may be a “view raw” option to show you what an email really looks like, and how it got to you.

There’s an example at the end…*

If you look at it, you’ll notice that because it’s filled as it goes along, it is not until the email is finally delivered that can you actually see the path it took.

In other words, if it gets lost, then it’s well and truly lost and virtually impossible to track or find.

With 300 Billion of -anything- it’s inevitable that thing will go wrong with some of them. That’s just the way the universe runs. In fact, that so many of them actually make the trip and get reassembled is pretty close to amazing.

In my 40+ years using electronic mail, starting long before there was a public-facing “internet” I’ve received well over 2 million emails. Every now and then one doesn’t arrive. However, I’d wager that it’s been less than 1 in 100,000.

When someone says “I didn’t get the email” chances are quite large that they are wrong. They got it and deleted it without reading it; it landed in their spam mailbox; it got filtered out by some over-eager host (looking at you Gmail and AOL!) But actually failing to reach the destination server is vanishingly rare.

I’m inspired to write this because today I saw something I’d never seen before: the SMTP server at our host was giving every email a high spam score, so our email was being filtered into the recipient’s spam box (well, depending on their own personal spam settings, of course.) VERY embarrassing for our host, and they scrambled to fix it.

Point is that I’ve never seen this in 40 years, so it was hard to diagnose, much less believe!

So: there you are – more about email than you wanted to know. But… now you know! 🙂

Tracy

Here’s the promised example email header:

Return-Path: <sender@someplace.com>
X-Original-To: recipient@someplaceelse.net
Delivered-To: x11354805@pdx1-sub0-mail-mx43.g.SomeMailService.com
Received: from vade-backend20.SomeMailService.com (fltr-in2.mail.SomeMailService.com [66.33.205.213])
(using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits))
(No client certificate requested)
by pdx1-sub0-mail-mx43.g.SomeMailService.com (Postfix) with ESMTPS id 41EE298071
for <recipient@someplaceelse.net>; Tue, 4 Jun 2019 14:54:01 -0700 (PDT)
Received: from bonobo.elm.relay.mailchannels.net (bonobo.elm.relay.mailchannels.net [23.83.212.22])
by vade-backend20.SomeMailService.com (Postfix) with ESMTPS id C5B794000021C
for <recipient@someplaceelse.net>; Tue, 4 Jun 2019 14:54:00 -0700 (PDT)
Authentication-Results: vade-backend20.SomeMailService.com; dkim=pass
reason=”1024-bit key; unprotected key”
header.d=photography.org header.i=@photography.org
header.b=LMOB8Jy2; dkim-adsp=pass; dkim-atps=neutral
X-Sender-Id: SomeMailService|x-authsender|sender@someplace.com
Received: from relay.mailchannels.net (localhost [127.0.0.1])
by relay.mailchannels.net (Postfix) with ESMTP id 62CE91A21EA
for <recipient@someplaceelse.net>; Tue, 4 Jun 2019 21:54:00 +0000 (UTC)
Received: from pdx1-sub0-mail-a16.g.SomeMailService.com (100-96-38-146.trex.outbound.svc.cluster.local [100.96.38.146])
(Authenticated sender: SomeMailService)
by relay.mailchannels.net (Postfix) with ESMTPA id B04AC1A23C3
for <recipient@someplaceelse.net>; Tue, 4 Jun 2019 21:53:59 +0000 (UTC)
X-Sender-Id: SomeMailService|x-authsender|sender@someplace.com
Received: from pdx1-sub0-mail-a16.g.SomeMailService.com ([TEMPUNAVAIL].
[64.90.62.162])
(using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384)
by 0.0.0.0:2500 (trex/5.17.2);
Tue, 04 Jun 2019 21:54:00 +0000
X-MC-Relay: Neutral
X-MailChannels-SenderId: SomeMailService|x-authsender|sender@someplace.com
X-MailChannels-Auth-Id: SomeMailService
X-Shoe-Bottle: 400ba0ab50630a71_1559685240240_2338004666
X-MC-Loop-Signature: 1559685240240:1840485062
X-MC-Ingress-Time: 1559685240240
Received: from pdx1-sub0-mail-a16.g.SomeMailService.com (localhost [127.0.0.1])
by pdx1-sub0-mail-a16.g.SomeMailService.com (Postfix) with ESMTP id C8E06800BE
for <recipient@someplaceelse.net>; Tue, 4 Jun 2019 14:53:55 -0700 (PDT)
DKIM-Signature: v=1; a=rsa-sha1; c=relaxed; d=photography.org; h=from
:content-type:message-id:mime-version:subject:date:references:to
:in-reply-to; s=photography.org; bh=5L7HIklL0wCkU0ypcRkIUoRmaA8=; b=
LMOB8Jy2TBpllKQwm9NNS5plG3ibBzvke7p3apYYyOXM5246LJCNx8jCnLulvZjL
jR/C0lk0bai/zKfV+qYtxZjWAocbwKIQLXQjYc8tSEEJ2gcDeq0Ej7kLxeYGHHgQ
ognij93JyNKQv0w8M204mQ2AKoOC5kKV1fx1A41dpyk=
Received: from [192.168.1.32] (c-73-241-48-152.hsd1.ca.comcast.net [73.241.48.152])
(using TLSv1 with cipher ECDHE-RSA-AES256-SHA (256/256 bits))
(No client certificate requested)
(Authenticated sender: sender@someplace.com)
by pdx1-sub0-mail-a16.g.SomeMailService.com (Postfix) with ESMTPSA id 4D9467FF46
for <recipient@someplaceelse.net>; Tue, 4 Jun 2019 14:53:55 -0700 (PDT)
X-DH-BACKEND: pdx1-sub0-mail-a16
From: Some Person <sender@someplace.com>
Content-Type: multipart/alternative; boundary=”Apple-Mail=_FBA4BD6B-A8CB-4FEF-A76D-040F73951B06″
Message-Id: <413A4AE3-03A9-49BD-98E8-3C5660A48123@photography.org>
Mime-Version: 1.0 (Mac OS X Mail 8.2 \(2104\))
Subject: Re: discount code for IJE
Date: Tue, 4 Jun 2019 14:53:54 -0700
References: <70A1983D-549E-4C11-B0A2-B2CAB33267B8@photography.org> <A56A1316-5331-45C3-AEF0-184CE3B838A5@photography.org> <DA021C83-189F-455F-B622-2494C6596FD4@photography.org> <703A1595-7095-4485-A964-6210EEA3ABED@photography.org>
To: Tracy Valleau <recipient@someplaceelse.net>
In-Reply-To: <703A1595-7095-4485-A964-6210EEA3ABED@photography.org>
X-Mailer: Apple Mail (2.2104)
X-VR-OUT-STATUS: OK
X-VR-OUT-SCORE: -100
X-VR-OUT-SPAMCAUSE: gggruggvucftvghtrhhoucdtuddrgeduuddrudeguddgtdefucetufdoteggodetrfdotffvucfrrhhofhhilhgvmecuggftfghnshhusghstghrihgsvgdpffftgfetoffjqffuvfenuceurghilhhouhhtmecufedttdenucesvcftvggtihhpihgvnhhtshculddquddttddmnecujfgurhephfgtkfgguffffhfvjgfosegrtdhmrehhtdejnecuhfhrohhmpeetnhhnucflrghsthhrrggsuceorghnnhesphhhohhtohhgrhgrphhhhidrohhrgheqnecuffhomhgrihhnpehphhhothhoghhrrghphhihrdhorhhgnecukfhppeejfedrvdeguddrgeekrdduhedvnecurfgrrhgrmhepmhhouggvpehsmhhtphdphhgvlhhopegludelvddrudeikedruddrfedvngdpihhnvghtpeejfedrvdeguddrgeekrdduhedvpdhrvghtuhhrnhdqphgrthhhpeetnhhnucflrghsthhrrggsuceorghnnhesphhhohhtohhgrhgrphhhhidrohhrgheqpdhmrghilhhfrhhomheprghnnhesphhhohhtohhgrhgrphhhhidrohhrghdpnhhrtghpthhtohepthhrrggthiesphhhohhtohhgrhgrphhhhidrohhrghenucevlhhushhtvghrufhiiigvpedt
X-VR-STATUS: OK
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X-VR-SPAMCAUSE: gggruggvucftvghtrhhoucdtuddrgeduuddrudeguddgtdefucetufdoteggodetrfdotffvucfrrhhofhhilhgvmecuggftfghnshhusghstghrihgsvgdpffftgfetoffjqffuvfenuceurghilhhouhhtmecufedttdenucesvcftvggtihhpihgvnhhtshculddquddttddmnecujfgurhephfgtkfgguffffhfvjgfosegrtdhmrehhtdejnecuhfhrohhmpeetnhhnucflrghsthhrrggsuceorghnnhesphhhohhtohhgrhgrphhhhidrohhrgheqnecuffhomhgrihhnpehphhhothhoghhrrghphhihrdhorhhgnecukfhppedvfedrkeefrddvuddvrddvvddpjeefrddvgedurdegkedrudehvdenucfrrghrrghmpehmohguvgepshhmthhppdhhvghlohepsghonhhosghordgvlhhmrdhrvghlrgihrdhmrghilhgthhgrnhhnvghlshdrnhgvthdpihhnvghtpedvfedrkeefrddvuddvrddvvddprhgvthhurhhnqdhprghthheptehnnhculfgrshhtrhgrsgcuoegrnhhnsehphhhothhoghhrrghphhihrdhorhhgqedpmhgrihhlfhhrohhmpegrnhhnsehphhhothhoghhrrghphhihrdhorhhgpdhnrhgtphhtthhopehtrhgrtgihsehphhhothhoghhrrghphhihrdhorhhgpdhhvghloheplgduledvrdduieekrddurdefvdgnpdhinhgvthepjeefrddvgedurdegkedrudehvdenucevlhhushhtvghrufhiiigvpedt

–Apple-Mail=_FBA4BD6B-A8CB-4FEF-A76D-040F73951B06
Content-Transfer-Encoding: quoted-printable
Content-Type: text/plain;
charset=utf-8

Hi Tracy,  (here the actual email, finally!)

ATV 4 Apple TV HD image is faded; washed out; no contrast; foggy… a fix?

My Apple TV 4 (ATV4) hooked up to a 4K TV looked like everything was filmed thru fog. “Shot through scrim” as they say. No contrast, no vibrancy.

Well, looking around, as you likely have, this is hardly uncommon.

I tried the whole range of adjustment, (as you likely have) without any luck.

Last night I figured out what it was.

Now, I’m not saying this will fix yours, but I -am- pretty sure that this is at least the gist of the problem, and perhaps armed with that, you can apply this to your particular setup.

My setup runs the ATV4 in to a Sony AV amp and out to the input HDMI on my TV. This allows me easy switching of my Tivo, ATV4, DVD player and Xbox.

The issue is HDMI itself, and how Apple vs your TV (vs your AV unit if you have one) implements it. HDMI is (at least in part) the industry’s attempt to keep you from playing pirated video (among other “safeguards”.) To this end, it isn’t a “simple pipe” of the audio/video signals, but a sophisticated chit-chat, where one component talks to the other and even coordinates how things will work.

Well, when that coordination isn’t just right, you end up with famous foggy picture: no contrast; washed out color etc.

My amp has a buried setting for each HDMI input. (I’m suggesting here that your TV may have this too, so keep reading.)

My amp had a setting for “standard” HMDI input, and “enhanced” input (ie 4K/HDR). If memory serves, my setting was, in fact, “enhanced.” But I decided to check the inputs for my other devices, and did find one set for “standard.”

What all this mucking about did however was this: it lead me to go to the HDMI input for my ATV4, and toggle it; to switch it to “standard” and back again to “enhanced.” When I did that, the TV screen went black and then came back…

… in Glorious Color! The fog was gone!

So that toggle caused  the “chit chat” between devices to start over, and reset things properly. THAT is what I discovered, and which I hope will apply to you as well. See if your AV-amp has similar settings. If you don’t have an AV-amp in the circuit, and you’re going from your ATV4 right to the TV, then see if you TV has an HDMI setting that makes a distinction between the quality/type of incoming signal (my “standard” vs “enhanced”.)

In fact, some TVs have a single specially marked HDMI input for HDR/4K.

Finally, before you do all this, here’s the other important thing I learned: mucking about with the ATV4 settings breaks this delicate balance, so set your ATV -first- and then leave it alone.

The new OS allows you to choose “automatic dynamic range” or “original dynamic range” (aka “as shot’.) Choose the latter. Do NOT choose automatic range. Then quit messing with it.

NOW you can try what I’ve described above:
1) setup your ATV4 and leave it alone.
2) if you have it, set your amp or tv to “enhanced” (or the equivalent) mode for that input. (Perhaps that means choosing the “enhanced” input for your cable. )
3) Do what it takes to “toggle” that so the devices are forced to reset their communications. (Unplugging and replugging it? I dunno, that’s not how mine works, so I can’t testify to that bit.)

I’m no guru on this stuff, and don’t blame me if you try this and your TV vanishes in a puff of smoke…I’m just sharing what worked for me, and why I think it worked.

Good luck to you!

USB device won’t mount? Is your hub powered or not?

Here’s something I just discovered. Maybe it’s “old news” or maybe it’s “just me” but FWIW

Based on my own experience, there is a subtle difference between powered and unpowered USB 3.0 hubs: sometimes a powered-hub device is not recognized.

Specifically I have an external USB 3 trayless enclosure that I use for swapping in/out bare drives for backups and so on.

My process is, with the enclosure powered off, I insert a drive. Power it on; wait for the drive to appear on the desktop; use it; eject it; and power off the enclosure before removing the drive. Wash, rinse, repeat.

The enclosure was been plugged into a powered USB 3 hub, and that “mostly” worked. But many times, I’d insert a drive and power up the enclosure and the disk never appeared on the desktop. Unplugging and replugging the hub caused things to work again.

I noticed something similar with USB flash-drives (sticks) as well, when used with powered hubs, so it’s not just this one enclosure.

A few days ago, I switched to an UN-powered hub… and everything “just works” now.

I suspect that a powered hub may present a unchanging signal of some kind to the device, and that in turn prevents a new device from being recognized. Perhaps the continual power makes it difficult for the system to recognize that the device has been -removed- instead. I dunno, but I do strongly suspect that something like that is going on.

Devices that do -not- have their own power switch/supply seem to have no problems at all with a powered hub.

As usual: YMMV.

Tracy
www.valleau.art

Tired of trying to remember passwords?

Tired of trying to remember website passwords? Does the thought of long, complex passwords intimidate you? Are you using “IL0VeYou” as your main password? Does the thought of a different password for every site bring up images of the Spanish Inquisition?

How would you like to be able to choose (say) your banking website from a menu, and never have to enter your name and password? How would you like to have impossible-to-crack unique passwords for every single site, and -never- have to remember any of them?

Sound like magic? Too good to be true?

Nope. It’s available now, both in free and paid configurations. It’s software called a “password manager.” Once you start using this kind of software, the -only- password you’ll need is the one that unlocks your account with it. From there on, it’s all automatic.

For example, when I want to log into The Center for Photographic Art website, I just choose it from a bookmark, as usual, but the software remembers my name and password and fills it all in for me. Even better, the software will come up with passwords the bad-guys will never break, like “bjTArzcU4{73Ud28xDUgM”. Of course I can’t remember that, but the point is I don’t have to remember it: the password manager software remembers it for me, and fills it in when it’s needed.

Stolen and hacked passwords are a reality. I’ve lost money because some of mine ended up in the hands of evil dudes.

Here are links to both free and paid password managers for both Mac and PCs.
If you are not using one of them… why?

Top two recommended first in most lists:

LastPass. Free and paid.
https://www.lastpass.com/
and
1Password. Paid (with free trial)
https://1password.com

Dashlane. free and paid
https://www.dashlane.com

RoboForm. paid
https://www.roboform.com/

Sticky Password. free and paid.
https://www.stickypassword.com/

___________________________________________

Finally…

Want to see if your password has been stolen? Visit here:

https://haveibeenpwned.com/Passwords

Want to see if your email address is well known?

https://haveibeenpwned.com/

Safari won’t play some videos

 

If you are using a recent version of Safari web browser, you’ll notice that some videos will not play. This is true not just on one site, but on all sites that embed videos. Here’s the fix:

The problem with videos is a “feature” of Safari. The recent versions have autoplay turned off.

To fix it, visit the site where the video will not play.
Under the Safari menu in the upper left of your screen, select “Settings for this website…”
Click the dropdown next to “Auto-play” and choose: Allow All Auto-Play.

 

Moving away from webmail and/or archiving your emails

On using email:

Today I was backing up my server, and noticed that some clients have over 1 Terabyte of email.

Honestly, I’m surprised their email has not slowed to a snail’s pace, and been kicking up all kinds of errors.

What happens is this: every email you get is stored on the host’s email server. If you don’t do something about it, you can end up with 15, 20, or 30 THOUSAND emails, and each time you log in, they ALL have to be accessed; each time you search, they ALL have to be searched.

Things just plain bog down. At some point, you’ll end up getting a warning notice from the host to “clean out the stables.” Automatic mechanisms take over from the ISP and move older email out.

Here’s how you to get around that; how to archive and backup emails; how to move them from the server to your computer: Use an Email Client.

Unfortunately, if you are accessing your email ONLY by webmail (using your bowser) then you’re in trouble: your only option is to -delete- old emails, losing them forever. In some states, that is, in fact, illegal for businesses.

If you use an email client…

With an email client, the process is -extremely- simple: drag the emails from your INBOX to a mailbox -on your computer.- Yep: that’s it.

In fact, with an email client, you can automate this using “rules” (aka “filters”) so that emails that meet any given criteria you choose, can be routed directly to your chosen mailbox on your computer. That way you never have to worry about the server filling up with old, outdated emails.

If you use webmail exclusively…

If you use webmail because it keeps others out of your email, you’re still doing it the hard way, not to mention permanently stuck deleting, instead of backing up and keeping archives of your correspondence.

I >strongly< recommend you set up an email client on your computer instead of using your browser.

You can still create password protected email boxes using the client.
This will allow everyone to use the same computer for everything, >except< email.

If you want to protect more than just email; if you want only some things on a single computer available to only some few people, the process is to set up separate users. All modern operating systems, Windows and MacOS, offer the ability for separate users to have completely independant environments on a single computer.

But, if ALL you care about is email, then create a separate profile for each user in Outlook. Functionally, this exactly the same as you are doing now with webmail: signing IN, and then signing out.

Once you are using Outlook or Thunderbird or whatever client you choose, you’ll find organizing, tracking, replying and so on are MUCH more elegant and useful… and you can automate your archives.

For example, I have every single non-spam email I’ve ever gotten going back to 1993, and it’s all automated!

Here is how to do it on a Windows system, using Outlook:

___________________________________________

If the user needs to share a common desktop, then the best way is to create multiple Outlook profiles and then configure them with different email accounts. The user has to setup a password for the PST files within their profiles, so that other users would not access them.

Refer to the following article ‘How to create and configure an email profile in Outlook’ and check if it helps:

http://support.microsoft.com/kb/829918

To setup a password for the Outlook data file, refer to the following link:

http://office.microsoft.com/en-us/outlook-help/set-a-password-to-help-protect-your-outlook-information-HA102749452.aspx

The other work around is to setup/create multiple Windows user accounts for the users on the computer and then configure their respective email accounts in Outlook. In that way each user would only have access to their own User profile.

To create additional Windows user accounts, you may refer to the steps mentioned in the following article:

http://support.microsoft.com/kb/2782153

fixing the color on Roku TV : the TCL49S403

The TCL49S403 Roku TV is a heck of a deal for less than $340: 4K and almost 50″.

But it comes with flaws. First is the limited viewing angle: you need to be sitting nearly  directly in front of it to get any pop to the image at all. 30 degrees off center, and the picture quality goes to hell.

There is nothing that can be done about that – it’s in the hardware.

And second,  the color is, shall we say, less than spectacular out of the box. And the build-in controls don’t do much to help it. 

The color was “adequate” (the most commonly used word in reviews) but that was about it. And my 4K Apple TV was pretty much terrible (a big idappointment because that is why I bought the TV in the first place!)

But I’m not here to bitch – I’m here to serve. I got my Roku  TV serving up splendid colors, and I’m a happy camper.

To do that, I had to choose some unusual settings from the TV menu, and then (the real secret) use the advance settings which are only available from your Roku App on your phone!

One of the nice  features of the TV is that these setting can apply independently to each of the HDMI ports, so you can have unique settings for each of your devices.

I’m not saying that -my- settings will match -your- hardware, but I’m pretty sure they will set you off in the right direction

HDMI 1 (My Tivo box)

Brightness-brighter
PICT mode – sports
Gamma – 2.2. (2.4 is a bit too dark)
Noise reduction – off
Color temp – cool
Dynamic contrast – off
Backbite – 100
Brightness – 50
Contrast – 95
Sharpness – 60
Color – 65

HDMI-2. Apple TV

Brightness-brighter
PICT mode – bright hdr
Gamma – 2.4*
Noise reduction – off
Color temp – normal*
Dynamic contrast – off
Backbite – 100
Brightness – 50
Contrast – 95
Sharpness – 82*
Color – 69*

 

NOW… on your iPhone, first select the HDMI input  your’re going to adjust, and then try these settings in the 11-point color secction:

20 x 15 x 20. (Normal)
25-25-25. Cmyk

In short, you’re bumping up the color intensity by those percentages.

 

I bumped up the “Custom” setting in CMYK, and chose that for my Apple TV, and bumped up the “Default” setting by 20-15-20. (It was a little too green for my taste, hence the 15.)

I hope this helps someone else as much as it has helped me.

Using your NAS to develop websites

Most people think that network attached storage (NAS) is just a box with drives in it attached to your local network. In fact, NAS is a computer, minus the monitor and keyboard. As such, it can be incredibly powerful, containing its own CPU and memory.

I recently found another good use for my NAS in setting it up as a Web server to use when I develop websites. I added Apache, PHP, mySQL etc, and several virtual hosts for the various sites. (Yes, there are software solutions such as MAMP and XAMP, but these have conflicts with your mySQL database, if it is already in use.)

So, by having everything on the NAS, it is completely independent of my machine and serves as a more realistic test bed.

The most interesting thing, however, is that I set up my NAS as a DNS server too, allowing me to use my mac’s web browser and type in my development name for each site, such as site1.dev or worksite.dev, while still allowing me access to the internet as a whole. The Synology NAS will forward through to a web based DNS if it is unable to find the requested site locally.

Then, all I had to do was go to network settings on my Macintosh and change the DNS to point at my NAS instead.

I thought that was pretty slick. I can work on development sites as well as continue to surf the web without any changes to my workflow. Very convenient.

FWIW.

How to move emails from one ISP to an other

The other day, I moved a client’s domain from one ISP to another; from A to B. That involved moving their email addresses as well, while keeping them identical between the previous ISP “A” and the new ISP “B”.

Convenient as that is for the client, there’s one issue: all their email prior to the move are still on IPS “A”.  After the move, if they look for their mailboxes, they will all be empty.

Not a good thing.

Here’s how to move their old emails to the new service provider:

(You can do this on your own computer, BTW.)

Create two email accounts, one for the old ISP “A”, and one for the new ISP “B”. Obviously, the will be identical – same name; same password; and same address.

With one exception.

for ISP “A” -the previous ISP- the server address must not be the URL, the domain (which now points to the ‘new ISP) but instead needs to be the IP address of the previous email server.

So, if you were moving “mycompany.com” to a new server, and the email account accessed “mail.mycompany.com” to do the transfer, you’d have the new one still use “mail.mycompany.com” but the account you make for the old one would be “123.222.476.930” or whatever the direct access address is. (That may not be an IP address per se; it might look more like “mailserve.oldip.net”.)

Then, using your mail client, log into both. Wait a bit until the old email populate the inbox for the old account, and then just drag and drop them to the inbox of the new account.

That’s all there is to it.

notes:

1) I suggest that you verify success by accessing the new account via webmail. 

2) some email clients are better than others at mass moves. (MailMate for Mac has no troubles at all.) Outlook, OTOH, may required that you drag-n-drop in small batches.

As usual, YMMV. This worked for me without any trouble at all, but the risk of using any of my suggestions is entirely your own. Etc.