Email Servers





Within Internet message handling services (MHS), a message transfer agent or mail transfer agent (MTA) or mail relay is software that transfers electronic mail messages from one computer to another using a client–server application architecture. A MTA implements both the client (sending) and server (receiving) portions of the Simple Mail Transfer Protocol (SMTP). The terms mail server, mail exchanger, and MX host may also refer to a computer performing the MTA function. The Domain Name System (DNS) associates a mail server to a domain with mail exchanger (MX) resource records containing the domain name of a host providing MTA services.

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eMails being rejected.

Is this problem on my end or the other end? What should I look at or what message should I send them? Is this my server or theirs?

   ----- The following addresses had permanent fatal errors ----- <>
    (reason: 550 Rejecting for Sender Policy Framework)

   ----- Transcript of session follows ----- ... while talking to
>>> DATA
<<< 550 Rejecting for Sender Policy Framework
550 5.1.1 <>... User unknown <<< 503 Bad sequence of commands
Exploring SharePoint 2016
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Dear Experts,

How to configure forwarding the email from (OWA) of an organization to an external organization email adress. For example, I want to configure email via OWA to both are different domain .

Many thanks in advanced.
can anyone help me with setting up email on a windows server so i can send emails from web pages, i have working pages but after moving to the new server they can no longer send as the server isnt configured..

Thank you
We have a mailbox that multiple users use.  Google G Suite asking to verify if its me when setting up for a new user.  I'm not sure who this Motorola Mot X is.  Is there any way through the admin interface to fix this and remvoe the Moto?  How do we prevent this scenario from happening in the future?

Google, Verify its you
Hi Expert,

My exchange server 2016 (192.39.X.X) can't receive email that are triggered from my internal server 192.168.X.X, however this is working in previous email system. the system email and internal mailbox are all at the same domain name

The email is triggered from my internal server scheduler to send email to exchange server internal user mailbox.
This scenario works in my previous Mdaemon email system, in the internal server/application they modified below setting to have the email triggered to internal users mailbox. i changed the application setting to point toward exchange server. but there's no email received for or
Configuration file in application:-

    <!-- Email Setting -->
    <add key="ServerName" value="" />
    <add key="Username" value="" />
    <add key="Password" value="XXXX" />
    <add key="Port" value="25" />
    <add key="EnableSsl" value="false" />
    <add key="SupportEmail" value="" />

How can i make this work in exchange 2016?

the emails take a while to delivery to outside, the emails internal delivery fast but when we send to clients o gmail, hotmail or some other take a while, which could be the problem?

I check the queue viewer in exchange and take a while to delivery at least 10 minutes but the emails are delivery after sometime
Been awhile since I have done a Exchange migration (little rusty), and getting use to the new Web interface for Exchange Admin Center. Seems I have an issue with internal mail. Here is the breakdown of our setup.

We are migrating to Exchange 2016 from Exchange 2010 (just the two exchange servers). I have Installed Exchange 2016 on the new Exchange server. Changed DNS entrys for “mail” and “autodiscover”, Imported SSL certificates. Running both in coexistent. All 2010 email and OWA works fine (as it did before on 2010 Exchange box).
Exchange 2010 server name is Eagle1.  Exchange 2016 server name is Eagle16.

I have move one mailbox over to new Exch2016 server database for testing. I can send and receive all email from outlook and OWA to outbound sources. (no problems externally).

Internally I can “Receive” email from other mailboxes on exchange 2010 server, but the test mailbox (on 2016 server) cannot send email to any internal mailboxes. (2016 test mailbox can’t send email successfully to the mailboxes on 2010 server).

Now again, I’m a little rusty, but the send and receive connectors all look good (as far as I can tell).
Not sure if I need to do anything with the IIS server. The test mailbox gets the 2016 OWA, and all other users get the 2010 OWA (they are still on Exch2010 server).

I did find this while fumbling with Exchange PowerShell. Looks like test emails are staying in queue (all to internal 2010 mailboxes), and when I look closer at queue, I see …
Dear Team,
I made an exchange Migration from 2013 to 2016.
I migrated all the system Mailboxes and started migrating all the users to new DB.
But i am frequently getting an error. below in my outlook.
The Microsoft Exchange Administrator has made a change that requires you quit and restart Outlook

Can you please help me sorting this out.
I have multiple  g suite email addresses and want them in one place, the problem with outlook, allow less secure app needs to be turned on, but since I have 2 step verification on the option to allow less secure app is not available, currently I am using windows 10 mail which does not require allow less secure app but it's a poor app for exemple it's search same is with subfolders and more, and suggestion?
We have a user who is complaining  they are not able to do a search via key words in their archived email, but it does work in their regular EMAIL.
They said they have tried via OWA and they keep getting no matches found.
They did report that they tried the search of a keyword with a verified email but they keeo getting the same message.
We are running exchange 2016
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In trying to set up Outlook (part of Office 365) on my new computer, I get an error message (see below).  I manually double-checked that the Yahoo settings are as provided on the Yahoo site, and double-checked to make sure that the email address & password are correct.  Can you figure out what else might be causing this problem?

Outlook Mail Error

Using my gmail account to send an email, is it possible for the recipient to know which country I sent the email from if I was travelling?  The same question applies to any any provider other than gmail.
I have an email account. It has the form:
In order to login to the email I have to browse to the website and, in order to log in to my email I have to enter the following details:
password: password1 [This was a password of my choosing]
Despite the fact that I provide authentication details on the website, once I am authenticated, I am diverted to a Gmail account with the company logo in the top right corner.

I would now like to transfer all of the emails from this (Gmail) account to another new, personal Gmail account. In order to do that I have been into the settings of my new Gmail account and used the "Import mail and contacts" process. The authentication details that I then provided in order to fetch the mail from the pop server were:
password: password2 [This is a random-looking password provided to me by the company]
pop server:

I successfully managed to set the "Import mail and contacts" process going. Unfortunately, it only transferred two thirds of the emails. Gmail did not provide any error message. It took me a while to work out that the company Gmail has a 30GB limit whereas the new personal Gmail has a 15GB limit and when it reached 16.5GB, the import stopped.

I purchased the 100GB package. Once this was in place, the import did not start up again. When i tried to start it off again, I just ended …
I'm using Office 365 and some emails from one external domains are getting quarantined.

We have enabled DKIM, DMARC for our domain.

When I checked the header information of the emails stuck in quarantine, I get error:  "DKIM-Signature Body Hash Not Verified".

When we click on more info on the error: It says to Add dkim monitor for

I need to know where exactly we need to add the above information i.e. in the DKIM which we created in Public DNS under the selector or this has to be done by the remote domain since they already have a DKIM for their domain as well. But emails from their domain are getting quarantined in our office 365 with the above error.
Hi Guys,

Because off an extended power failure, our Exchange 2016 mail server was moved to a backup site.
The server IP was changed (LAN), but nothing else changed.  Issues started to appear, such as OWA opens, but we are unable to send / receive mail.
Mail to the send connectors under mail flow settings also stopped working.

We recently migrated Exchange 2013 to Exchange 2016.
Exchange 2013 gave several errors and not starting some services, but we left the server running whilst transferring mailboxes to 2016, etc.

Exchange 2016 is running from a "backup" DC in the backup site.

Upon clicking new e-mail in OWA, the new mail window opens, but clicking "send"  - nothing happens.  
The e-mail does not go to the Sent Items folder, neither does anything comes into the inbox.

No specific errors in the event log (Exchange 2016)

No configuration changes happened on the 2016 server, except for an IP change for the LAN.

My question,
After one upgrades say Exchange 2013 to Exchange 2016, and Exchange 2013 has not yet been uninstalled,
What affect does it have on the mail flow and mail transport?
All mail flow receive and send connectors have been updated to the 2016 server.
I am trying to send email through an application on the server.

From: ABC
Reply to:
Domain: internal

user: db.admin
password: password for this ad account

I get following error on test email:

javax.mail.AuthenticationFailedException: 535 5.7.3 Authentication unsuccessful

It looks like I am not able to authenticate using this account db.admin ? or is it something else ?
I am running exchange 2010.

Could it be the possibiltiy that this account is not authorized to use SMTP relay ?  If yes, where in exchange 2010 exactly I can go and see all the accounts those are authorized ?

Thank you!
Dear Experts

I am hoping someone can assist me with the following issue. I have SPF and DKIM configured on my domain, which appear to be setup correctly but when I examine the message header of an email I sent I see the following entry "None ( does not designate permitted sender hosts)"

Just to add I am using Exclaimer for signature management.

Please can someone examine the header below and advised if I configured something incorrectly.

Received: by 2002:a4f:c15:0:0:0:0:0 with SMTP id 21csp930979ivm;
        Wed, 21 Aug 2019 06:30:56 -0700 (PDT)
X-Google-Smtp-Source: APXvYqyk6Zvuz4Zzp1WUwoJQlz3EsF/mENO5B7uNOXkWXKiQUJ9CmIl25//eS3gDvDa/NqaFIZJg
X-Received: by 2002:a17:906:158c:: with SMTP id k12mr31626198ejd.83.1566394255976;
        Wed, 21 Aug 2019 06:30:55 -0700 (PDT)
ARC-Seal: i=2; a=rsa-sha256; t=1566394255; cv=pass;; s=arc-20160816;
ARC-Message-Signature: i=2; a=rsa-sha256; c=relaxed/relaxed;; s=arc-20160816;
I have an Exchange 2016 DAG setup with 2 servers having the "Content index state" failed and suspended.
Actually on server1 it is failed, and on server2 it is suspended.
Using Exchange powershell commands to catalog the DB did not work most likely because no valid index is available.

What should I do to fix this?
problem started 2 days ago, we are currently using mapilab to redirect our incomming emails from external smtp to our exchange server.. emails are not being sent to users, instead its going to C:\MAPILAB IN\Bad folder .. to fix this temporarily, all i have to do is to restart the Microsoft edge transport services and that would solve the issue. Later on, it became worst, i had to restart the server to fix the issue. Checked the mapilab logs, im getting the insufficient resources error.. checked drive capacity, still have 59gb free.. i also checked online for some solution and that is by editing the edge transport config thru note pad and adding the required line so it wont check resources, that didnt work.. also tried to see if i can just manually move the incomming mails to the default pickup folder C:\Program Files\Microsoft\Exchange Server\V15\TransportRoles\Pickup and that didnt work as well.. so I am running out of options now, i just need a temporary fix then later on during weekend, i will move the entire database to a higher capacity drive..
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I have an older exchange server which is working without a problem on my current ISP.  I had to switch ISP's recently and my old ISP will be disconnected shortly.

Unfortunately, even though I WAS told my new ISP can provide rDNS for my on-premises email server, I am now being told they cannot.

I have a "persistent-IP" which is ALMOST a static public IP, but it must be from a block of public IP's they have in which I am probably being natted.

So, is there a way to setup a third-party rDNS so my emails from my on-premises server do not end up in spam or bounce?

Dear Wizards, we have an Exchange 2016 server, domain:, after times, Boss wanted to change email domain to, then we configure the Accepted domain in Exchange server to; but the AD server 2012R2 still is

Now, we would like to change the AD to as well, but still keep the Exchange server working.

Is it possible? if so, can you suggest please? Many thanks!
I've selected details like
but I encounter issue below. Why?
Our organization is using Exchange Server 2013 and each user requests delivery and read receipts. We've had weeks/months where it worked flawlessly (at least they didn't tell me it wasn't working). Then a month where they get the read receipts, but not the delivery receipts. Then the same thing only sporadic over the course of a week.

We had a ticket open with Microsoft last year about it and they remotely connected in to our server and confirmed the settings were correct to allow the receipts on our end, but they also noted the tracking receipts for users are unreliable as well as dependent on the recipients server.

That being said we've got read and delivery receipts from the same external users, then not received them. In that example the external users are a local company across the street from us so we confirmed with their IT that they allow delivery/read receipts.

I am officially stuck at this point and the big guys are getting upset now. I've been trying to talk them into a third party solution, but penny pinches are pinching. Is there anything I can do to on my end to dig further into this?
Hi Experts,

I have two servers running Exchange 2016  and Exchange2019.
All mailboxes and public folder on the EX2019.

Question: Is Impersonation working with EX2019 ?
Because on my end not or I have something forgotten within the upgrade.
Any Ideas ?

When I test with EWS-Editor, IMPERSONATION is working to the EX2016 but not to the EX2019.
I would like to know if it is possible to find an open smtp relay in internet that i can use with telnet to test if there are any issues with our antispam hardware.
thank you in advance

Email Servers





Within Internet message handling services (MHS), a message transfer agent or mail transfer agent (MTA) or mail relay is software that transfers electronic mail messages from one computer to another using a client–server application architecture. A MTA implements both the client (sending) and server (receiving) portions of the Simple Mail Transfer Protocol (SMTP). The terms mail server, mail exchanger, and MX host may also refer to a computer performing the MTA function. The Domain Name System (DNS) associates a mail server to a domain with mail exchanger (MX) resource records containing the domain name of a host providing MTA services.