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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Hello everyone. I have an issue where our company emails are sporadically being sent to the recipients junk email folder. There is really no ryme or reason, I can send an email and it goes to the junk folder, then send it again a couple hours later and it goes straight to the inbox.

I have verified our domain is not on any public blacklist\greylist. We use O365 and mimecast. I have verified our DNS, SPF, etc. records.

Does anyone have any ideas on what could be causing this issue?
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i have two Exchange Server 2016 installed, i need to enable pop3 on ports 110 and 25, it keeps asking me username/password  whereas i am giving right info.

My Exchange is not live yet, so i am using public IP to access it instead of hostname.

i can telnet to both ports from the internet on 110 and 995

On Remote connectivity Analyzer it's not allowing me to do the test since it does not allow me to enter IP of server only, instead of hostname.
On exchange shell, if i run test-popconnectivity the following will go success:
Test-PopConnectivity -ClientAccessServer exchange-dr -lightmode -MailboxCredential (Get-Credential)
Test-PopConnectivity -ClientAccessServer exchange-dr -lightmode -MailboxCredential (Get-Credential)  -PortClientAccessServer 995

but following will fail:
Test-PopConnectivity -ClientAccessServer exchange-dr -lightmode -MailboxCredential (Get-Credential) -PortClientAccessServer 110

The error is:
                                                              Authentication failed.
                                                             The connection is being
                                                             The handshake failed
                                                             due to an unexpected
                                                             packet format.Server
i lost connection to my exchange 2010 server. all the users cant connect to outlook. so i went to the server directly to connect and the EMC and EMC shelll would not connect. I can't do anything. I try to use elevated command on powershell and cmd but i cant. Please HELP!!!
My brother-in-law has forwarded an email conversation to me that was initiated by a request for the payment of an invoice that did not exist. The spam email appears to have come from his email address and was sent to people in his address book. I was wondering if someone could help me to recognise whether the spam email is a spoof or whether someone or something has managed to hack into the email account. I have no real experience of reading email headers so please be gentle.
Thank you in advance.
Single exchange server.
5 e-mail domains
Two mx records
One spf record in one „primary“ domain public dns.
Spf v=spf1 mx –all

What about other 4 domains

I think that someone trying to spoof this 4 domains e-mail addresses and sends spam.
Do I need to add spf record to other 4 domains and how to configure spf for other 4 domains.
Outlook makes appointments private when dragging to a delegate calendar on the outlook.
I have a email list with around 5 million that I want to send out for marketing. do u know what is the most affordable way to send them out efficiently?

I know like mail chimp and other can get this done but it is just too expensive to us
Dear Experts
We are having issue on CRM system not able to send mails through the configured SMTP server but the network team says the issue is from CRM application side however to come to the correct conclusion,
Used Telnet to test SMTP
1.On the CRM hosted Windows OS system did the telnet check with smtp host and port , it connects also performed following steps I,e setting smtp server , source domain, senders email and recipient email, message subject and body we are able to send and receive email
Please let me know the above steps does it passes through SMTP authentication OR not
2. configured email account in the CRM system with SMTP mail server.port: (SMTP server is
check marked "use SMTP Authentication". provided user name and password  the result  is not able to send mail following popup from the CRM system
"Error Failed to connect to outbound SMTP Mail Server. The outbound mail server selected for the mail account you are using is invalid check the settings OR select different mail server" BUT when unchecked the "Use SMTP Authentication" that is disabled the SMTP Authentication then able to send mail out..
As mentioned above SL1 when able to send and receive email from telnet does it passed though the authentication , please help.
Hi I am migrating from Exchange 2010 to 2016, all is going well except when I have users outside the network, and their mailbox still lives on the 2010 server, the 2016 server acting as a proxy using owa it asks for a password prompt when the OAB is downloaded by Outlook.
Hi I have worked in the capacity of  Microsoft Exchange server and AD for sometime, but recently have received additional duties and one of them is reading email headers. For example making a determination of why an email was blocked, tagged etc.. on firewall appliance. Any guidance on where I can receive resources to learn RFC's and how internet email work. I don't see a lot of material but only unix resources like postfix and sendmail. I I have been kind of winging it and using google but would like some more formal information about this stuff.
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I set a new IMAP configuration through Outlook 2013 for one of my clients. He originally had a POP3 setup.

My client stated he was wasting allot of time updating his desktop Outlook after he made changes (read, delete, send, etc.) on his iphone, hence the move to IMAP.  

The transition was not easy! He had massive custom folders (including sub folders) under his inbox containing client emails over the years. He is basically keeping a history via his outlook. I ran into a ton of problems attempting to restore a PST backup to an OST IMAP account - too long to explain. At a certain point I was moving one folder at a time/counting emails. I finally got to the finish line. All the folders/emails were synced to the online email server.  As I'm about to report the great news, my client tells me he opened a suspicious word document which turned out to contain a virus.

So...I had to buy new drives , and perform a full restore of  recent backed up images. I bring the system back on line, it performs an outlook sync and proceeds to freeze up the on-line email server web account (purchased through a 3rd party vendor). I am now unable to access any folders, or emails either through the web interface (to a 3rd party email server) or through Outlook. I called up the 3rd party, who stated they will refresh their server. I await the results.

In hind sight, I feel like I should have kept those custom folders out of the sync process. At this point, it feels like a total mess.

We are using Exchange 2016 CU10 on-premises but could not setup the email signatures (only images) on OWA.

When we compose an email, the signature image showed up but when the recipient got that email (on both MS Outlook 2013, 2016 and OWA), it showed the X red icon, instead if proper image.

Can you please suggest? Many thanks!
I'm receiving the following Error when installing Exchange 2016. Let me Describe what all has taken place.

We sat up a 2012 server and installed Exchange 2016 on it. It Ran fine but we did not do any migrations to it at all. Then one day we went to start things on it and it was gone from our VM'S didn't even have the .vmdk or anything. So we spun up a new server 2016 and gave it a totally diffrent name and went to install exchange 2016 and that is where we are today with the following error in the attachment.
Dear Experts

We have configure CRM application system running on windows server R2, configure the application for outbound and inbound in the email settings section of application  but mails are not getting delivered from CRM system to SMTP server , log report attached, from the OS level when done telnet able to communicate to the mail server, can you please suggest where we might be going wrong and help us to fix this.
Hi Guys
We have a strange issue at the moment. We run Exhange 2016 on prem and have a number of users who only use email via OWA.

Randomly some users cant reply, forward or even send emails.  It’s different users, at different times with th different error messages.

I’ve seen loads of posts online with similar issues but the main consensus is that it disappears.  I can’t really accept that so I’m wondering if anyone has any ideas of where I can look to troubleshoot, or if any hot fixes  etc exist.

Any advice would be much appreciated.


I am testing Google Cloud Directory Sync (formerly Google Active Directory Sync) to sync AD users (only) to our G-Suite.

The AD users are polled and have emails ( in their 'mail' attribute.

All AD users already have a G-suite account with the same email.

However, the GCDS simulation log states it will suspend all users?!

What am I missing?

I thought if GCDS sees an existing G-suite account with the same email it would leave it as active?

Any help would be greatly appreciated.
We are using Exchange 2013,
From couple month ago, our Online Web App have an issues which is after success login, it will goes to all blank page.
only online web app (OWA) have this issues, exchange control panel (ECP) does not.

However certain browser is able to login successfully and display inbox interface (Internet Explorer, Android Default Browser).
Other browser like Google Chrome, Firefox, Apple browser Safari will appear blank screen after success login.

Any advice from experts?
Outlook 2016 will not connect to Exchange 2016. When attempting to set the user up (Never had this version of Outlook) it fails saying the credentials are could not be found.

The user can connect to Exchange through:

Outlook Phone App
Built-in Mail client on Windows 10
Previous versions of Outlook

Just not Outlook 2016
I have an "hMailserver" running.
It has two jobs:
1. receive "local" emails, which are stored on that machine as ".eml" files and are processed by some software
2. relay emails addressing an external address to be sent out to the internet

The concept is basically working fine.
However, I have problems of getting the relayed emails accepted by the recipient's provider.
From Microsoft I get "banned email". From Google I don't get any message, but the email does not arrive.

The machine (running hMailserver) is sending above emails from a machine, which has no certificate.
Is that a possible reason?
Or do I have to configure something in addition?

Many thanks for any help
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Exchange 2016 CU 9 DAG  2 Nodes

Getting this event over and over everyday

Log Name:      Application
Source:        MSExchangeTransport
Date:          9/6/2018 7:01:45 PM
Event ID:      8019
Task Category: RemoteDelivery
Level:         Warning
Keywords:      Classic
User:          N/A
Creating extra connection for idle queue: 1147 with queue type: DnsConnectorDelivery and next hop domain: raspberrypi. Current number of connections is: 1
Event Xml:
<Event xmlns="">
    <Provider Name="MSExchangeTransport" />
    <EventID Qualifiers="32772">8019</EventID>
    <TimeCreated SystemTime="2018-09-06T23:01:45.334613800Z" />
    <Security />

Open in new window

Any ideas?


I would like to add a BCC list to the following Powershell script:

$SMTPServer = ""
$SMTPPort = "587"
$Username = ""
$Password = "password"

$to = ""
$cc = "","", "", ""
$subject = "Subject here"
$body = "Insert body text here"
$attachment = "C:\Users\User1\Desktop\Attachment\Attachment.pdf"

$message = New-Object System.Net.Mail.MailMessage
$message.subject = $subject
$message.body = $body
$message.from = $username

$smtp = New-Object System.Net.Mail.SmtpClient($SMTPServer, $SMTPPort);
$smtp.EnableSSL = $true
$smtp.Credentials = New-Object System.Net.NetworkCredential($Username, $Password);
write-host "Mail Sent"
Hi,  Iam creating workflows in Jira and I want as port of the flow to send an Email to the operation team once any change has been planned. But I want it to use various field and free text boxes to guide the user in creating the email.

So my idea is that when the use hits "ready to implement) a form pops up with various fields pre filled such as requestor name and date / time of change) and other boxes free texdt or drop down. then once thes user fills in the form and clicks submit Jira created the email and send it to a pre defiend email.

Is this possible to create email body on the fly based on a pop up form?

Thank you
I have an email server that I wan't to send messages via multiple SMTP smart hosts that I own and that are installed on different host.

So the basic setup is

Server 1  -----> smart host 1 ----> user mailbox
                -----> smart host 2  ----> user mailbox
                -----> smart host 3  ----> user mailbox

Server 1 is installed on Centos 6.9 on which I'm having problems correctly setting up exim route_lists. What I have now doesn't work.

  driver = manualroute
  domains = ! +local_domains
  transport = remote_smtp
  route_list = *
  host_find_failed = pass

What I want is when I schedule a message in Server 1 and choose multiple smart hosts (inside the software) to take care of the sending, my messages to be routed to its designated sending relay without returning errors like "550 relay not permitted".

Any kind of help would be highly appreciated.

Thank you!
I need CMD for exporting all mailboxes to pst in certain DB in exchange 2007 services pack2
Dear Experts,

I was tasked to find out if this email is genuine or not.

I tried to send a test mail to both email addresses, my boss was not happy about that.

I did a nslookup and had the following info     MX preference = 10, mail exchanger =     MX preference = 15, mail exchanger = internet address = internet address = internet address =      internet address =      internet address =      internet address =      internet address =

What other methods can I do to check and confirm if the email sender is genuine or not?

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.