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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.

We just completed a migration for a client from POP3 to Office365.
I cannot 100% say that some accounts were not imap, but everything I touched was POP3.

It was a manual process that required both email servers to be live with transport rules between them.
There was no easy way around this, but only Office 365 exchange is running now.

During the process we would fire up an O365 license for the user
Import their PST into the email account through Outlook
Let it migrate to the cloud
and everything worked fine save for 1 other user that had this issue.
Deleting and recreating their profile solved the problem for that user.

Current issue
One user had a sizable PST of around 11GB, but nothing we had not seen in several other users
It imported to Outlook without error

In Outlook 2016, there is an issue where SOME subfolders not showing any emails.  Even when a brand new email from today is moved to that folder.  Invisible.
All of the emails show up in OWA.

We have deleted and recreated the email profile
Set cache to ALL (changed from 1 year)
Set cache to none
View->view settings = Off.  Do not see any filters set there.
Do not see any rules set up

I have noticed that some of the subfolder properties show
Type: folder containing IMAP items
Where others show Type: folder containing Mail and Post items
However they do not correspond to the problem folders.  It appears to be random which will not sync and which have the IMAP or…
Hi Experts,

I am lately experiencing something very strange and frustrating with my Outlook (Office 365).

When searching for emails I definitely have them in my inbox, for no money can I find them.

Just this Friday I sent and received back messages with subject "Email wording", and when searching for it or by going thru all my Friday emails, I simply cannot manage to find them.

Any Idea?

I just joined 1 company where I see 3 DAG eachDAG having 15 member servers and around 300 databases in eachdag

So to confirm there will be 900 databases altogether?

I need to come up with a plan to patch these exchange servers

Can anybody share how to patch in batches and any architecture over iew will suffice

How will I  ressed thr databases in each DAG

Also I need to remove tls 1.0
dependencies from send and receive connector

How should I do
we have exchange 2016 in our environment.

but we were told to enable mapi over https?

isn't exchange 2016 had this feature enabled already, i was told to do for certain CAS mailboxes only.

i believe exchange 2016 doesnt have CAS mailbox?

we did migrate from exchange 2013 to exchange 2016, any idea the CAS mailbox are from there?

2nd question

i have been told to disable TNEF ( rich text) in our exchange 2016 organization( winmail.dat file) - any reason ?
I am trying to find a user friendly software that can explain SMTP logs to better understand what is going on with some emails. This is for an email relay server. We have some emails that didn't reach the other end but I do not see any errors on the logs. Is there anything you recommend?
i want to do OS patching on DAG  which has 100 exchange servers  which are windows server 2016.

we are deploying vulnerability patch

do we need to put mailbox servers on maintenance mode as well?, will failover occur as well.

do we need to migrate PAM ?

any steps would help

This is related to https://www.experts-exchange.com/questions/29173852/phpmailer-mailbox-unavailable.html

I’m testing sending out automated emails from http://selfregistration.iwscc.ca/email_test/index.php but not all are going through. For example, when I send to aleks@iwscc.ca I get “..mailbox unavailable or not local…”.

Please ignore “email sent” in this instance, because I quickly wrote the script without any error testing. However, it is sending to the following

aleks@aces-project.com (hosted by Microsoft, also mailbox is not local, but working)

apdcompany@gmail.ca (hosted by Google, not local and working)

One thing that I found strange when receiving the credentials for aleks@iwscc.ca as user is that said that if I want to encrypt emails, I need to purchase SSL. I know usually the SSL is for the server side, not client side. I am thinking that maybe that the iwscc.ca is some type of a budget server, but I cannot see how this relates to my script, which is at another server, and it should come down to sending a regular email. Manually, you are  able to email aleks@iwscc.ca.

What could it be?
I don't know where to post this question so posting it in C#/.Net Programming.

I want to purchase this domain postmaster@doctoraccessnow.com  from gmail --> https://www.domain.com/email/gsuite-by-google-cloud

1. I go to Domains --> Search for your Domains and search for postmaster@doctoraccessnow.com

2. I get this that the domain is available but you see...the @ is removed. I don't want to purchase it without the @


Is this correct? am I doing it correctly?
We attempted to send a large amount of email out to our customers last night through our Exchange 2016 server. Everything went well except for a single queue, comcast.net. It sent the majority of the email out, however it is now stuck with the attached image. We have already restarted the transport service as an attempt to correct the issue. Any advice would be greatly appreciated.

Exchange Error Message
Dear Experts
We are implementing exchange server enterprise 2019 on-premise and for security and barracuda email security appliance (at DMZ)
Please help on which all the ports to be opened at firewall and as well between email security appliance and email servers, please help on following
1.      From firewall to Barracuda email security appliance and from email security appliance to firewall
2.      From barracuda email security on premise appliance to on premise email server
3.      From on premise email server to barracuda email security appliance
4.      From email server to internet
please help on the above, thanks in advance
I've got a user who's email is hosted through their ISP & is having email issues.
When trying to send & receive, he's getting the message;
Your mailbox is temporarily unavailable because another email message is being delivered to it or another email application is accessing it.
The server responded: -ERR [IN-USE] account is temporarily unavailable.
Called tech support who couldn't tell me anything other than asking me to check the incoming & outgoing ports & has to escalate to level 2...
Nothing stuck in outbox,
It looks like he's getting messages to his account via the webmail page, although none of the ones I've sent have shown up
Any suggestions?
I have an CA issued certificatthe that is used for SMTP Email  on smartphones.  That SSL/TLS Certificate is to expire in about 2 months n the future; but, all of the sudden iphone devices cannot get the comapny email(Send/Receive).  This problem does not happen on Android Devices.

Not all apple devices have this problem but many do.  I could not find an obvious and consistant pattern, if it was the version of the IOS or anything like that.   But it appears that Apple updated their Security requirements for SSL: https://support.apple.com/en-us/HT210176

No SHA-1 certificates are valid with IOS version 13.0 and higher.  I have 13.3 on my iphone and my iphone still works just fine but other iphones with that version do not.

I think the solution is to upgrade the CA-Certificae which we are planning to do anyway; but, is there a work-around that that we can configure in the mean time?  I wonder if one can downgrade the version of the Apple Iphone IOS until the new certificagte is in place?

No android devices have this problem and some Iphones are still working (for now).  Is there a work-around we can use until the new certificate is prepared and installed?
I have a customer trying to send email to me using his Yahoo email and he got a bounce.  

What is the best way to see if his email address is being blacklisted?
Dear Experts
We are in process of implementing on-premise exchange enterprise email server for this we have install SSL certificate, please suggest which provider and what type of ssl certificate should we have to go for exchange enterprise email server. thanks in advance.
I disabled a mailbox in Exchange 2010. I am trying to reconnect it but I cannot find the mailbox to reconnect. The disabled mailbox had no mail in it because it was new. I can't login to my EAC console because it doesn't seem to like my login credentials. I tried running the clean command to update the databases to show the disabled mailbox in the EMC under disconnected mailboxes but nothing seems to work. I had to make a change to the AD User account so I figured I would disable the mailbox till I made the change.
What to check further, due to issue below to get Email message?
I have a problem sending email attachments from my Outlook account to various Yahoo email accounts.  The email arrives fine, but the attachments are somehow corrupted into something that cannot be opened.  Below is a screen shot of the message I get when I attempt to download a PDF file, though the same happens with Word attachments.  And there is no "open" option available.  It seems as though all the attachments are renamed to some version of "di-mail.ymail.com":

Yahoo Attachment Problem
Please help.


There should be a log out option here under the email address. I only took one action and cleared the cache on Fire Fox earlier today.
Hi Experts,

I have to migrate migrate several mailboxes from DOMAIN A to DOMAIN B. Cross-Forest.
The user will stay in DOMAIN A but the mailbox is migrated to DOMAIN B.

We have nearly 200 mailboxes to do.
But in the meantime I have to test this.

How can I test the mail flow ? The MX Record is still showing to DOMAIN A.

Do you have any ideas ?
Any help to error below?

"ERROR"      1544      "2020-02-14 16:06:28.994"      "Severity: 1 (Critical), Code: HM5028, Source: ADOConnection::Connect, Description: Error when connecting to database. Microsoft OLE DB Provider for SQL Server Cannot open database "hMailserver" requested by the login. The login failed. Check your database settings in hMailServer.ini."
We are running MS Exchange 2010 in a DAG environment. We are running our Exchange environment with update rollup 13.
Exchange Update Rollup 29 for Exchange Server 2010 SP3 was accidentally downloaded and installed to one of the Exchange servers in the DAG. The problem caused by rollup 29 being installed is users that have their mailboxes that server are  not able to access OWA.

When I try to uninstall Rollup 29, I get this Error message:
"Setup wizard for update rollup 13 for Exchange Server 2010 Service Pack 3 (kb2141339) ended prematurely."

I other words, when attempting to uninstalling Rollup 29 which I don't need, setup tries to uninstall rollup 13 which I do need.
Exchange server with several domains due to business name changes and several mergers over the years. My question is how to configure incoming email to show up in the users Outlook inbox depending on which email (domain name) they're sending to. For example, user@domain1.com was the default format. Over the years the names of the business changed to user@domain2, later user@domain3.com. I'm now getting ready to make the default domain @domain4.com. I've configured everything, tested and email is working fine. I changed the default domain to @domain4.com.

Is there a way to have the original sent to email show up in users inbox. For example, if I send an email to user@domain1.com, user@domain2.com, or user@domain3.com it always shows up to the end user as coming from user@domain4.com. The end user would like to know which email the sending is sending to rather than receive all emails appearing to come from the default domain (@domain4.com).

I have this alert from microsoft

Activity: MailRedirect
User: abc@nnn.com
Details: MailRedirect. This alert is triggered whenever someone gets access to read your user's email.

I checked the user mail account in office 365, but I did not find any forwording. I checked Mailbox permissions and I have "There are no additional mailbox permissions set on this mailbox."

So what excatly is this alert about ?

Please help
If someone manages to compromise your user credentials/account via a phishing email (office365 email account in this case) what is there typical objective(s) in doing so, and how would they typically follow that through to the next stage. I would have assumed if there target would be to steal emails they would not just casually start forwarding them on to an external address?  Trying to determine what they may or may not do if they do get a victims credentials would be interesting. there must be something in it for them but to determine what that is and how they execute 'phase 2' once access is achieved would be most useful,
is there a specific security role in office365 which would allow our risk team to run message trace requests and also have complete unrestricted to the various audit logs, such as the unified audit log. e.g. that mentioned in here:


it would be also useful to identify the current auditing settings, e.g. what is and what is not being captured, so identifying

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.