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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I'm looking for a SMTP test tool which:

- Can use TLS connection
- port 587.
- can add username /pw

Any idea where I get a that tool?
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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;
My office has been using Exchange to run our email system but a month ago we switched to our own domain and moved our email system to that domain.

We're using Outlook as a client.

Meanwhile I had not cancelled the Exchange subscription and now we're getting 2 separate and unique sets of emails to the same single email address.

It seems that anyone who replies to the "mail on the old server" will have their messages routed to the "old mail server" inbox. And anyone who replies to the "mail on the new server" will go to the "new mail server" inbox.

1. If I cancel the (old) Exchange subscription, will "all NEW replies to the mail on the old server" be automatically routed to the "new mail server"?

2. What is the most efficient method to combine the two sets of mail? Is there a software or specific way to bring the "original server mail" to combine with the "new server".  I don't want to risk deleting or overwriting a bunch of old mail.

Thanks in advance for any advice!
Problem: Using Outlook to move an existing mail item from an Outlook PST or IMAP folder into a different Outlook IMAP folder causes the IOS native email client (INEC) to display the ‘wrong’ date/time – that of ‘now’, rather than the time when the item was received or sent.

Whether or not relevant, such a move also changes the item’s ‘modified date’ as displayed in Outlook as follows: a) A move whilst Outlook online changes that date b) A move whilst Outlook offline does NOT change that date upon the move, but does change it to the time at which you subsequently go back online. (and that time is also what is seen in IOS)

Possibly the iCloud server is imposing today’s date/time as described by Nicolson (Search Nicolson “RFC 3501 section 6.3.11” re: Gmail.)

However, some items in IOS display a different date from what Outlook shows as ‘Modified’, it seems likely that IOS is not using whatever variable Outlook uses for ‘Modified Date’.

Moving an item between folders in the same Outlook PST does NOT change the item’s ‘modified date’ as seen in Outlook.

Moving in INEC or iCloud Web: Moving a message between folders within Icloud Web or INEC does NOT 13change the modified date/time shown in Outlook IMAP folder, or the date/time shown in Icloud Web or INEC.

Gmail Behavior: By comparison, using Outlook to move mail items into Gmail IMAP folders also causes the Outlook ‘modified’ time to change. But the INEC client (and the Gmail app) show the ‘correct’ timestamp – …
We have an Exchange 2010 with a couple of receive connector.  I have configured one for receiving incoming mail from the Internet
Most of the incoming mail is working fine

The thing is that with some  remote domains (that seem badly configurated like the smtp FQDN banner is an invalid domain name (.local) or the reverse DNS does not match and these servers try the StartTLS the receive connector selected by Exchange is the "Default" one even thoug my "Default" one is bound only to receive from my local private subnet.  Checking Anonymous users permission this connector solved the problem  but that seems odd since it's bound to my local subnet only.  Server was checked and is not an open relay as the security right to relay has not been added on the Default Receive connector

Any logical explanation ?
Can a forward be placed on a Gmail account which has been moved the the Vault? (Leaver)

We have many cases raised for a shared mailbox type setup for a leaver's mailbox so that historical email and forwarding can be put in place for another staff member.
I'm receving the following error message when trying to amend the default email address policy on our new Exchange 2016 server.

'The recipient policy "Default Policy" with mailbox manager settings cannot be managed by the current version of Exchange Management Console.

How can I amend the default email address policy?
I have a costumer that forwarded her gmails to another user while she was on vacation. I went in the account and tried to stop the forwarding emails but there is no email so I can disable the forwarding but the other user is still receiving the emails.
Dear Experts, we have Exchange 2016 server on 2012R2 platform. Clients can access mailboxes via outlook (pop/imap/exchange) or OWA. After renewed SSL certificate, our users could not access their mailboxes via pop/imap anymore. Those services are still running on Exchange server.

When we tested the connection on MS outlook, it could login to server successfully but could not send test email, so I think there is something wrong with SMTP and SSL.

We tried to restart pop3/imap services but it did not help. Also tried to assign new SSL to SMTP but could not. Can you suggest?

we are having some issues connecting our printers with our SMTP server.
we are using port 587 and if configure the printer to use startTLS the connection will fail, without it just.
i tried to configure a receive connector on our exchange server with our printer banding and i assigned the SSL cserticect to the receive connector but still not working.
any recommendation?

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I am using this script to import distribution groups from Exchange 2016 crossforests. Everything is working including Contacts creation, adding and Primary SMTP address setup.

The only thing that's not working is the addition of the secondary smtp. I am getting the following error:

Exception setting "EmailAddresses": "Cannot convert value "System.Object[]" to type "Microsoft.Exchange.Data.ProxyAddressCollection". Error: "Conversion from System.Management.Automation.PSObject to
Microsoft.Exchange.Data.ProxyAddress has not been implemented.""
At C:\CrossForestMigration\Groups\DistributionGroupImportFrom.ps1:268 char:8
+ ... $GroupToUpdate.EmailAddresses = $GroupToUpdate.EmailAddre ...
+ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ CategoryInfo : NotSpecified: (:) [], SetValueInvocationException
+ FullyQualifiedErrorId : ExceptionWhenSetting
I have a particular user who is having email delivery issues. When sending a calendar invite or email to a another user (internal or external) they are getting the following:

Remote Server returned '554 5.6.0 STOREDRV.Submit.Exception:InvalidParticipantException; Failed to process message due to a permanent exception with message Participant is invalid: "Can't parse a participant from string """. Validation status: InvalidAddressFormat. InvalidParticipantException: Participant is invalid: "Can't parse a participant from string """. Validation status: InvalidAddressFormat.'

More info:

We are currently in the middle of a mail migration and currently have a hybrid exchange environment set up. The email delivery issue is appearing from the O365 exchange.
Please help me make a SMTP server.
I have a user who opens email messages that have been saved to a network location and they don't fully display. If you maximize or minimize it and then restore it to a window, it displays correctly. I've run diagnostics on the laptop and updated everything Dell has for this machine but the problem persists. It doesn't happen with messages in the user's mailbox. We save pertinent email messages in our various project folders. This appears to be the only user experiencing this
I have a php email contact form I am trying to get to work with GoDaddy,  I contacted their tech support and after a while they gave me the mail_test.php which gives every configuration they have.  I need help getting the SMTP portion of the mail_test.php to work with my script.  I am including all the info that is needed but let me know what other info is needed.  Any help is appreciated.

Here is my script for the mail contact form
    $to = ""; // this is your Email address
    $from = $_POST['email']; // this is the sender's Email address
    $name = $_POST['name'];
    $subject = "Form submission";
    $subject2 = "Copy of your form submission";
    $message = $name . " wrote the following:" . "\n\n" . $_POST['message'];

    $headers = "From:" . $from;
    $headers2 = "From:" . $to;
    mail($from,$subject2,$message2,$headers2); // sends a copy of the message to the sender
    echo "Mail Sent. Thank you " . $name . ", we will contact you shortly.";
    // You can also use header('Location: thank_you.php'); to redirect to another page.
<form action="" id="contactform" method="post"> 
                            <input type="text" name="name" class="textfield" id="name" value="" />
                            <div class="clear"></div>             

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I had this question after viewing Our Exchange Send Connector logs directory is empty.


I am tasked with decommissioning an Exchange 2007 server (yes no joke!), but before I do I need to ensure what hosts are using the SMTP receive and send connectors. There is one send and several receive connectors.

I have enabled verbose protocol logging on both the receive and send connectors. I have restarted the Exchange transport service and even the server (several times). The path to the logs are as follows:

ReceiveProtocolLogPath                  : D:\Program Files\Exchange\TransportRoles\Logs\ProtocolLog\SmtpReceive
SendProtocolLogPath                     : D:\Program Files\Exchange\TransportRoles\Logs\ProtocolLog\SmtpSend

The logs for the SMTPsend directory is empty and the smtp receive has 3 logs dating back to 2014. Nothing new is being generated. I have tried to create from mail traffic by running a telnet SMTP session to send tests mails (which runs ok).

Any ideas Im stmpted at this stage.

I am trying to set up scan to email on a network multifunction. The new multifunction is an upgrade so all the network settings were migrated over from the old one that was always able to scan to email and scan to a network file share. I put in the SMTP server and username and credentials. I put in the correct ports and made sure it  uses SMTP authentication and not POP or anything like that. It hasnt had any issues printing and it can scan to a network share but not to an email. From the machine itself it even does a succesfull SMTP server connection but it fails to scan and send anything to an email. BTW this is a Ricoh      Aficio MP C400SR.
How to decide to set dmarc to quarantine or reject? I am reviewing the dmarc reports but don't know what to set. Right now is set to none for collecting dmarc reports. What to do?
How can I use CFIMAP to read email? I I am starting off with trying to open a connection and then close it. When I try to close it I get an error that there is no connection. My code looks like:
server = ""
username = ""
password = "password"
connection = "conn"> 

connection = "conn">

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but I get the error:
there is no connection available with name [conn]

I have confirmed that I am using the correct server, username and password. I am hoping someone can tell me what I am missing.
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How do i find out if my linux server using sendmail or postfix to send email outside.

when i did send email out using the following command

mailx -s syslog-conf myemail < /etc/syslog/sylog.conf

I am getting "postdrop: warning: unable to look up public/pickup: No such file or directory

But i do see the file

we are using Mobile Device Manager Plus MSP. Our goal is to get mobile devices that are secure with no unwanted app and no change of system settings. The devices have only company email access. The phones are company owned so no BYOD.
For us the Kiosk mode was a proper solution for this.

Now we have 2 problems with email.
Since Android 8 Gmail seams to be the default email-config-setup app. So if you push the active sync settings and MDM will setup the password it will always open Gmail.
How can we change this or is there a work around?

We don't want to use the Gmail App, because the accounts settings are "open". This means you can add other private mail accounts.
So the other question is, what are other (enterprise) Mail Apps than can be configured with only the company active sync server?

Maybe the Mail App will also solve the first question :)

Thank you.
Is it Possible to restrict Views in Exchange Admin Center in a Multi Tennant Enviroment In Exchange 2019

I Have used RBAC To restict how the roles function However Administrator of Other Organisational Units can still see all other Tennants in Other Organisational Units

Even though they cannot edit it, We would like the Admin Of each Org Unit to only See Users of that Org Unit
My emails sent from my gmail account are not delivered to accounts

I send an email to ******* (my accoint too)

And it is never received. An my gmail account gets no undelivered message.

All other gmail accounts I have tried send to and are received fine.

Prodigy aupport says it is a gmail problem.

I am at a loss.. I ahve neve aabused my account in any way.

Is there a way to trace what happens one the emails are sent? To see where they are being stoppned from delivery?

We currently use EWS to move emails from the inbox of one mailbox to the inbox on another mailbox based on specified criteria. The code is as follows:

private void MoveEmailToAttacherMailbox(string id, string attacherMailbox)
      DocStore.Logger.Info(string.Format("{0} id: {1} To attacherMailbox: {2}", (object) nameof (MoveEmailToAttacherMailbox), (object) id, (object) attacherMailbox));
        Item.Bind(this.exchangeService, (ItemId) id).Move(new FolderId(WellKnownFolderName.Inbox, (Mailbox) attacherMailbox));
      catch (Exception ex)
        Exception exception = ex;
        DocStore.Logger.WarnException(nameof (MoveEmailToAttacherMailbox), exception);

Unfortunately since 29th November we have been getting an error: "MoveEmailToAttacherMailbox Microsoft.Exchange.WebServices.Data.ServiceResponseException: The move or copy operation failed."

No permissions have changed and the mailbox we are moving from has full delegate permissions to the mailbox we are moving to. Any assistance will be greatly appreciated.
In a Nation Builder nation, I have a 700-member e-mail recipient list. The majority of these recipients were imported when my nation was set up a couple of months ago. Email to these recipients is solicited because they all pay a monthly/annual fee for membership.

I've sent about a dozen email blast in this time without problem, and I get stats on how many people opened links inside the emails, how many bounces, how many are ad addresses. However a couple of weeks ago, I sent one out and it first reported everything to be OK, with zero bounced, but after about 4 days, the bounced shot up to 117. This was highly irregular because the highest number of bounces before this was about 8. I had a look at the 117 and they are all Yahoo, AOL or Sky addresses, and since AOL and Sky go through Yahoo, we can assume that this is specifically a Yahoo problem. Here's the message that appears in Nation Builder next to each bounce...

4.0.0 Email was deferred due to the following reason(s): [IPs were throttled by recipient server]

I've done two more blasts since this, and the same thing happens. I've checked with a few owners of these email addresses and can confirm that the emails are not being received.

Is there anything I can do to help this situation, either on Nation Builder, on Google G-Suite, or on Yahoo? I've contacted Nation Builder support, but all they suggested was that I send a handful of emails at a time in order to rewarm Yahoo. But this could take a long time, …

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.