Email Protocols





Interactions between email servers and clients are governed by email protocols. The three most common email protocols are POP, IMAP and MAPI. Most email software operates under one of these (and many products support more than one).  The correct protocol must be selected, and correctly configured, if you want your email account to work.

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After reboot, I got this error in Exchange Management Console, also I could not login to OWA, it showed blank page when I entered correct username/password.

All Exchange services are running. Environment: Exchange 2016, Window Server 2012R2

Can anyone help, please?
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Does Migration Wiz migrate all emails, calendar items, contacts, tasks, etc. from Gmail into Office 365?

Or does it only migrate emails?
Dear Guys, we are deploying Exchange mail server. We knew that the Mail server must be published with an public IP address (and registered with A, MX, TXT records) but is it mandatory for an Active Directory (of mail users) Server to also have an public IP address and to be registered (by A record) in domain control panel?

Many thanks in advance,
I am having an issue with getting vcenter emails working. Vcenter 6.0. Mail server is set to a ip of a working iIs smtp relay for another application.  The working iIs smtp is working for 10 other server applications. Logs are saying "550.7.60 client does not have permission to send as this sender". I granted the vcenter ip relay permissions on the smtp server. I can't figure out why vcenter emails can't make it's way out the smtp server but the other applications can using the exact Office 365 email account. Thoughts?
I had a spam problem about a month ago, which I fixed on my end.  I notice now that email I send to recipients at gmail are automatically being marked as spam.

My mail server is Unix - Communigate Pro running on an old PowerMac. Outbound mail goes to my SMTP server, which is a Dell SonicWall ES-3300    I changed the IP address after the spam got past the SonicWall, and put the new address into my DNS, which is hosted by

I looked at the header of a message I sent to my gmail account.  I see something wrong with the SPF record  

X-Mlf-Uniqueid: o201708020314430029673
Arc-Seal: i=1; a=rsa-sha256; t=1501643684; cv=none;; s=arc-20160816; b=fxKfyh5i6PzjoNNZkIMPSigH31cy4YQ3IwPn/XLlJekZPjdgLTVrCmwlzwGh2orLVN GAg7JYp8zmTIKmoj2fOo5/v5m9m+aMH16VJDa7PKxY2H5qYRt9OHehY+o6UqP95Il9lz 3/cqc1G6Fo+j3t0oCCa8H/JW4+03+o3X9nlX+ioY6gOoFGy7GtWzW4OJpxiJZUjxhtxp FgenvR03ekg/ZHQv7j3P/FIoDPhoQK/EzgofSx6a7qKwl0D4jY8YzBVvcQjfHYaJV96j porICVs9nghyv8bE7Oy34UxkqG3ZLJznTB4WqAmYzkC8Nw3duZRcC8G0B+ZXQXz1s7mi Jz0A==
X-Received: by with SMTP id p85mr27288566qki.281.1501643684625; Tue, 01 Aug 2017 20:14:44 -0700 (PDT)
Return-Path: <>
Arc-Authentication-Results: i=1;; spf=softfail ( domain of transitioning does not designate as permitted sender)
Dear Team, is it possible to import PST files which are more than 2 GB into Exchange server via Exchange Management Console? Many thanks in advance

In this article:, it said that "The PowerShell Command to import Outlook data file (.pst) to Exchange Server can’t import the file more than 2 GB."  

Can someone pls verify?
Dear Zealots, do you know any method to show the statistics in Google mail's usage. For details, we would like to have the report showing the frequency of email flows, like how many emails in weekdays and weekends, from 8 AM to 5 PM, from 5 PM to 10 PM, etc.

The same question in MS Exchange server. Can you please suggest? Many thanks in advance!

Update1: I found Gmailmeter, it could show me my statistics, but how can I see my end-users'?
Dear EE

Please can someone tell me what's the difference between the "From" and "X-Sender" field in message header?

We recently had a spoof and phising attempt on one of your users.

I have SPF in place and it works but it didnt stop this email because the X-Sender address is not that of my domain. My SMTP domain is

Please see image:

Where within the Gmail admin console can the external DNS mail exchange (MX) records be changed for an organization using Gmail for its email?
We have recently migrated from Exchange 2007 to Office/Exchange365. Since migration we have received a number of email rejections on one specific email indicating "your email program added invalid characters (bare line feed characters) into a message you sent".

The email itself comes from an HTML template and generated in Microsoft Dynamics AX. This is directed email to customers and is consistently accepted by some downstream providers (eg gmail, Hotmail) but not others (eg Yahoo, Comcast).

The HTML code that comprises the body text has been scrutinized and does not contain any bare LF's, nor has it changed since long before the migration.

Support from Microsoft, Yahoo and Comcast has been of little use (for the most part unwilling to engage other than throw out generalities to get you off the phone).

Key facts;
- email was working prior to (Exchange 2007 to Office365) migration
- other (text) email to affected customers is delivered without issue (ie limited to one HTML email)
- originating email has been checked for bare LF's

As this email was working previously I have the following questions;
- have you seen and resolved similar issues?
- As this was working previously I am wondering if Exchange 2007 stripped out bare LF's in order to fix (my understanding is that Office 365 was but stopped doing so).

Please do not suggest online articles found by Google searches unless you feel there is something very specific we can look at. We have searched …
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Am I wrong if understand "Archiving emails " in MS Outlook will reduce the .PST file by reducing its size?

If so, what is the real mechanism behind it actually?

Please help, wiZards. Many thanks in advance.
Called number from blog at Yahoo to see what I was doing wrong.  I had followed the instructions to the letter.  Verified pw on separate computer.  Tech tells me he needs to add services to account so this will work.  THEN he tells me if cost $149.00 for him to do this.  AM I being scammed and if so is there a special way to make it work.
We have a web application that uses the client email to send email 'from'. We want to add an SPF record on the client's DNS (text records) to allow this. I need to confirm the syntax before I do so.

v=spf1 a mx ip4:XX.XX.XXX.XX ~all

Open in new window

"domain" being their domain name
XX.XX.XXX.XX being the IP of the server that hosts the web application

Please let me know if you think this looks correct or if any changes are needed.. Also what is the difference between  and

Had issues with ActiveSYnc timing out on Exchange 2010 SP2 RU4. Updated the server to SP3 RU17 on May 20th.
Only the activesync timeout problem for 3 Users existed prior to this update. These activesync issues remain for the three Users (not the focus of this question) and new issues are seen (focus of this question):

Total of 15 Users out of 250+ affected with this new problem. These Users are not the same with the ActiveSync issue:
1) For SOME Users all shared mailboxes in Outlook no longer populate with emails or auto-update immediately after the updates.
2) For SOME Users, this issue appeared to start a full week later.
3) For ONE User, only one of three shared mailboxes in Outlook are not auto-updating.
4) Selecting the folder in Outlook ,choosing the 'Send/ Receive' tab and selecting 'Download Headers' then 'Update Folder', allows the emails in these shared boxes to populate with new emails (since the last time this process was manually run).
5) Win7 Pro for all but two Users, who are on Win10.

What I have tried (not necessarily in this order):
1) New Outlook profiles
2) New Win7/ 10 User Profiles. Tried this because loading two of these Users' profiles onto a different, unused laptop works fine.
3) Deleting the .OSTs manually and rebuilding
4) Cached Mode/ Online Mode
5) Deleting the autodiscover xml record in the Outlook profile folder. Did this in case that file was corrupted and was not pulling the shared mailbox info properly.
6) Saw a …
Hey Everyone,
 This started late last week all of the domains we host are unable to send out to AOL but we can receive aol email.
Ive checked all of our domains against blacklist as well as the server IP.

Any ideas on this ? I'm completely lost at this point and still waiting to hear back from AOL.  Is there anything I can check or do to rule things out?
Our mail service is server 2012 running smartermail.
my not-for-profit has 20+ service-focused email accounts for different business needs. Right now I keep about 10 tabs open on my desktop to monitor incoming traffic and reply when needed. Is there an app/dashboard (like Hootsuite) which I could use to create dashboards to manage these Inboxes?

I have a domain a purchased through GoDaddy. I then am using HawkHost to send and receive emails. I changed the MX records accordingly.

For some reason, I can send messages but I can't receive them? Any idea what would cause this? Is there anything other than the MX records I should be changing on GoDaddy?

Also kinda strange... if I do the Outlook "Test Email" the message ends up coming through. That is the only message that makes it into the inbox.
Dear Sir,

We have a software to send bulk emails to our clients which contains the course materials. When sending the bulk emails, there are lots of error/time-out which the destination mail server reject our emails. I've solved the problem for those by adding a record on our DNS server to proof we are not the spammer. But yahoo and hotmail not solved yet. Are they have this mechanism?

Thank you.

With regards,
recently my mail relay server experiencing incoming mail delayed from, as i see online forums, MS recently have stopped using TLS 1.0 authentication and only supports TLS 1.1 and 1.2, but not all of their servers but 75% of it, but my mail relay server doesn't have any TLS enabled, so is this can be the issue?

all the mails from other mail servers receive without any issue.

My mail relay server is CentOS 6.5 , (no Grey list enebled, no SPAM filter, no TLS enabled)
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how can I download all my gmails for offline viewing
Is there such a list of IP or smtp domains (doesn't have to be up to the hour up-to-date) list so
that we can block at our smtp?

Blocking by firewalls is not good as the emails will still come in
What's the easiest way to move from pop3 to imap on multiple devices?
Pretty sure the mac stuff (iphone, ipad & possibly mac book) are currently using imap, but the PC (desktop & laptop) is the one that makes me nervous. I can envision myself with hundreds, if not thousands of duplicate emails to sort through when its all said & done!
I get an email in outlook 2016 through my pop mail server (if that matters), with the specific email I am looking at sent from gmail... but I think this is a generic question.

On the to line, along with my name, it might show 'steve smith'; 'bob jones'; etc.... the other people it was sent to, with each name in single quotes (this is a group mailing)

Each is a hyperlink - i can hover on a name and a little window pops up with the contact image (just the default outline), and the mail icon is clickable.  A down arrow brings up a bigger contact window with that person's email address.

My question - where is it getting all those person's names?  From the sender's contact list? or is it matching to my contact list? Don't think that's the case, 'cause I don't have some of those people.

and when I send an email, is it also picking up the person's name and including it along with their email?

If I was to have a contact for 'bob (what a butthead) smith'  with email, when I type an email to bob smith, does he see that name I have for him!?

Is there a way to keep that from being sent? so he just sees it was sent to
Hi Experts exchange.  I have an application that sends emails upon completing a arduous process.  Ie.. we have to create a permit and inspect it and what not for the email function to fire off from the application.  Our email functionality has been suspect and I was wondering if there was a quick and easy way to send an smtp request to our smtp server from a command line to quickly test functionality without having to create the permit and inspect it.
Does anyone know how to do this.
the server is windows 2012.

if someone could type the syntax or command, that would be awesome.

example variables you could use.   the sendto address is   the smtp server address is  the hostname of the server trying to send the email is bigsun with ip address

those are fictious settings above but just wanted to be able to tie logic to syntax.
Can someone help me out.
regular gmail; not g-suite. one label.

gmail label

only want gmails to reach inbox from one sender

all the other emails are not important

is there a gmail filter using the word NOT

Email Protocols





Interactions between email servers and clients are governed by email protocols. The three most common email protocols are POP, IMAP and MAPI. Most email software operates under one of these (and many products support more than one).  The correct protocol must be selected, and correctly configured, if you want your email account to work.