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 discovered guerrilla mail tonight, and wonder how many people use it for a bitcoin campaign?
I looked at this outline page here


5. Buy/Sell Bitcoins in Cash

It seems ideal to me. I link it with my yahoo email. I think it last forever, but your emails disappear after an hour.
Will miscreants be able to swipe my BitCoins away?
Can they unravel it to find my identity? The FBI? I just want to have a bag for anonymous BTC donations.
I understand I can put an alias as my owner name?
Thomas Alva Edison? Davie Crockett? Scrotie Mac Boogerballs Puke Skywalker?
How does the IRS find out?
I'm not interested in earning outside of the law. Will bitcoins become worthless?
Build an E-Commerce Site with Angular 5
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I have exchange 2016.  I have a user that receives payroll info that is encrypted.  Those emails are not being delivered.  The spam company says they have handed it off.  I check the message tracking logs and that email doesn't exist there.  How can I verify the email was actually received or not during the transport from the Spam host to my exchange server?
We have 15 users all on POP3 accounts using ClassicHosting as our email provider and Outlook as our desktop client.  When we went to switch the first users we backed up their POP email and then set up IMAP with no issues.  We then tried to get the old email (from the pop account) however we were unable to import the old Pop email to the IMAP account.  We reverted back but there has to be a way to get the old email into the new format.  Any suggestions?  PS we are
This message on multiple home use/small business (no-Exchange/no-domain server) computers trying to access their email through Outlook 2016 via an Microsoft Office 365 Home subscription - on Windows 10 Home and Pro operating systems

dialog box
The certificates have valid dates

It does not seem to matter whether the accounts are imap or pop - same issues.

I have tried the solutions that mention AutoDiscover . I went looking on my Windows 10 registry and it has no entries under the  AutoDiscover registry keys...?

Everytime I help someone add Outlook 2016 to their computer, this is popping up and I have not been able to figure out how to get rid of the message.
I have tried installing the certificate for user and local machine and it does not solve the problem.

I am stumped.

It is annoying to have to say "Yes" to allow access every time you open Outlook.

I appreciate your help. TIA
My Exchange 2016 seems to be unable to sends email to a compagny and I notice that it could be because of the header which is different then others:
Total retry attempts: 16
Server returned '400 4.4.7 Message delayed'

Here's the header in question:
[Contacting []...]
[Connected] ESMTP Exim 4.91 #1 Thu, 14 Feb 2019 16:37:13 -0500
220-We do not authorize the use of this system to transport unsolicited,
220 and/or bulk e-mail.
I would like to know if there is an easy way or if this can be done? I would like to move(export) a .pst folder from my outlook 2016 to my documents or desktop. Can this be done? If so the easiest way to do that.

Thank you.

Basem Khawaja, R.Ph.

someone is spoofing my mail domain.
I have SPF record and it is not enough to stop spoofing.

I didnt know how spoofing is easy :-)

"Find a website like deadfake, which describes itself as “a site that lets you send free fake emails to anyone you like.
Or Or There are dozens. Many of them are free, some cost a little money to send mail.

    Enter your recipient’s email address in the To: field.
    Put whatever email address you want in the From: field.
    Craft your message and press the Send Now! Button.


So,what are my options?I have ptr and spf record.
To configure dkim and dmarc?
Any advice?
Please,can anyone explain how to implement.I have 4 email domains on mail server.
Is there any dkim&dmarc tutorial for dummies :-)
Thank you
I have a MicrosoftSQL table for notifications (FacilityProjectNotificationT) connected to Access through ODBC.  In that table I have a PeopleID (who needs to be notified) column,  ProjectID,  SubjectDateColumn, AdvancedNoticeDays (int), NotificationNeeded (bit), and Notified (bit).  We have many people that need to be notified about the current status of a project at different intervals across a project's lifespan.  For example, our commercial team needs to be notified 30 days before ProjectedCompletionDate in order to supply trucks for shipping product.  

I would like to have an additional column for "NotificationCriteria".  This would be something like: iif (Date() => ProjectedCompletionDate + 30 AND [Notified] = 0, [NotificationNeeded] = -1,  [NotificationNeeded] = -1.  I am not sure if all that is properly coded.  If possible, I would like to place that formula in the NotificationCriteria column and tweak it as needed for each individual.  My end goal is to automatically generate an email (I have all the email generation coding) that will notify these individuals of the upcoming Project Completion Date.  Each night, I'd like to run an Access File with an AutoExec event that looks for individuals needing updates and sends them an email.  How would I call the NotificationCriteria column's contents so I don't have to recode a specific email for each individual person/criteria?  Any advice on how to set this up or where to look where someone has done something similar?  I …
I'm looking for an expert to help me understand DMARC reports.  I believe I understand the concepts of DMARC, DKIM, etc. and have set everything up properly.  I'm receiving the DMARC reports and have also setup a free DMARCIAN account.  I've been review the data in there and between that interface and looking at the XML reports in Excel, I'm just not putting it all together.  Ideally, I'm looking to hire an expert that can get on the phone with me to help me understand these reports and answer some questions I have.  I have a very good understanding of email, DNS, etc. but just can't figure out these reports.  Someone that understands DMARCs very well would be a great fit for this.

thank you!
Dear Experts, I could not delete the message in Exchange 2016 like before.

Here is the screenshot, yellow square is the user mailbox, blue square is the distribution mailbox. So what are the differences between DROP and SEND in Agent tab?

The second screenshot was the result after issued command to delete, it said success but the message was still in the recipient's mailbox

Can you please suggest? Many thanks!
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Last week I opened my Outlook email (pop3) and noted that I had around 1700 unread messages, I thought, oh boy they found me expecting to find a ton of spam, but no.

While much of it was spam, a great deal was email I wanted to get, and it all arrived that day but was sent as long as 6 months before.   This was from sites like zip-recruiter, dominos, Dell, and multiple other domains.

I have been receiving mail from all of those sites, these were messages that simply sat somewhere in limbo?  

I changed my email password.  But I have no clue as to why this happened, or if it is going to happen to others, where do I look for answers?  The server logs only indicate that they all arrived the day they did. It seems like they were being "held" somewhere.

technical notes:  I do have my account on my phone (IMAP - turned that off), using ALT-N Mail Daemon (not exchange), NO one else (132 users) has reported this issue or anything even similar.
I am running an Exchange 2013 server and have a 3rd party app that needs authenticate to use SMTP. If I encrypt authentication using STARTTLS it works. If I use TLS it won't authenticate. The certificate is assigned properly and the receive connector seems to be configured correctly as well. We're going through port 587 and I have no logs from the application. Just a message saying it couldn't authenticate.
The user received a legitimate email with a return address using their text mail address. However they didn't send the email, they only received it.  The sending address is their phone number @
The user has an iPhone, an iPad and an iMac.  The email was received on the iPhone and iPad, but not on the iMac.  

Is there a way to see the header on an email received on an iPhone or iPad?

They have since called AT&T and made sure that they don't share their phone number account with anybody else.
ATT told them that they also share a satellite TV account with another person, but that this other person is the only control for the shared account.

The user changed their iCloud password, and confirmed that they have 2-factor authentication turned on.

My guess is that their phone number is embedded in the Mac Messages app on some computer somewhere, and that when a file was 'shared' the Messages app sent the file using a wrong phone number.

Naturally, they don't want people sending out email using their AT&T phone number

Any idea how this return address appeared?


email with text mail address
I would like what is the normal behaviour when you send an email from MS outlook 365 to Onenote? Is the email supposed to remain in outlook after it is saved in Onenote OR is it supposed to be deleted from Outlook?
Got a user with a account, trying to set up on Outlook 2010 with no success.
I've seen slightly different settings out there, but again, none are working.
Is Outlook 2010 even compatible with a account?
On hMailserver, I have
but  now it is leading to problem below
when sending out mail (within server). Before this, it was fine to send out mail on server
Is it possible to investigate who a certain e-mail address belongs to?  My client is receiving emails from people trying to impersonate their employees by sending emails from addresses that are very similar to those used in the company
The user has just set up a gmail account, and is looking for software to pick up their incoming AOL email, and then automatically redirect the mail to their gmail account.

They have a computer that is always on and always connected to the Internet.  It would be great if this software could run as a Windows service or Mac OS X daemon.

I've got a user with their personal email (through Comcast) set up on;
Home computer
Work computer
Email is currently POP3 & the fact that mail isn't synched between all devices has started to bug him. I suggested changing to IMAP, but don't want any hiccups along the way, as that will have him freaking out!
What's the cleanest way to make this transition?
Any particular order to do the devices in?
Should I export his pst (for safe keeping or any other reason) before embarking on this journey?
Any advice appreciated!
OWASP Proactive Controls
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Learn the most important control and control categories that every architect and developer should include in their projects.

Email sent to a Yahoo user are received showing HTML formatting.
Is there a way to determine the cause?

Possible clues:
a CC: to an AOL user
An attachment

Here is a sample of what the message looks like, followed by the raw message:  

<blockquote type="cite">
On October 19, 2018 at 12:13 PM Office Person < > wrote:
<div class="">
Dear Debbie,
<div class="">
<br class="">
<div class="">
Please find attached the initial Listing of Subject Matters, signed by Mxxxxx.

Raw Message below:

X-Apparently-To:; Fri, 19 Oct 2018 16:17:12 +0000
Return-Path: <>
Received-SPF: none (domain of does not designate permitted sender hosts)
Hello Experts,

My client runs an on premise Exchange 2016 organization with several MBX servers in a DAG. The issue is that a single user did not get the typical email message when she connected a new phone and tried to use the app Outlook for IOs and Android. For security reasons, company does not allow to sync devices with this app, and a mobile device policy was setup to prevent sync and an email automatically goes to user's mailbox.

Situation is that we can see the new device is in quarantine as expected, but user never got the email "Your device is temporarily blocked from synchronizing using Exchange ActiveSync until your administrator grants it access"

We performed an email search against this mailbox for the dates that she was supposed to receive the email, and the search did not return any values.

Other users are not experiencing this issue.

Any ideas?

Found the 2 links but they do not state how to resolve this issue or find a logical explanation

starter unlimited plan

Is the email safe?

If I upgrade to
Business unlimited
Premium unlimited
is email more secure

can someone visit a webpage and see my email
using a browser or telnet or command prompt window
Dear Experts

We have been provided to configure email account in CRM system to send email through the SMTP server using  office365 connector ( SMTP Relay ) the provided account is of without the password (hence in CRM system configured without SMTP authentication) , we were able to configure this account in CRM system and able to send mails but the messages are not getting stored in sent items. to achieve this should we have to go for Authenticate CRM application directly with an Office 365 mailbox, and send mail using SMTP client submission please suggest, thanks in advance.
I have critical situation , suddenly any user cant receive mails in my organization , i have exchange 2007 i can send mails but nithing reicved even internal
what i can do
i review all settings which was used before and it is up and running
Dear Experts, we have several Exchange 2016 servers (VMs) in Vsphere 6.5 environment, but one SAN storage is running out of space.

How can I check whether if we can delete some space in Exchange Database? Due to company policy, we have to keep disabled mailuser for a year; but in urgent they can be deleted.

But I'm not sure to check the space which was taken by those disabled accounts. Can  you please help? many thanks!

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.