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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.

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my memory utilization is around 7gb  on hub transport servers  (they are on VMware)as per solar winds report

how much memory should I add into it
 can I increase to 16 GB and how should I change the page file
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I am getting below error on my2010  exchange server which is DAG

Error Description: MS Exchange DB integrity check: [\\?\GLOBALROOT\Device\HarddiskVolumeShadowCopy1567\DB\IME.DB02.edb start ... ] ...
Hello Experts,
One of the particular database was in Failed state so stopped the search services and deleted the CI CUID directory in an effort to rebuild the search catalog, but now just goes right back to crawling for more than 24 hours now.
The database size is 2 TB.
We also have passive but in FailedAndSuspended State.

Is this normal and how long will it take before turning to Healthy again? Any ideas would be appreciated.
Dear guys, we have an Exchange 2016 on-premise server and would like to increase the attachment's size of users' emails to 100 MB. We did some research and followed but still got the error "The following files weren't attached because adding them would cause the message to exceed the maximum size limit of 25 MB: smex_12.0_ag.pdf. " when attached a file that is bigger than 25 MB into an email. Could you please suggest?

Attached pictures are our settings, we restarted IIS, Transport services, even server itself but did not help!

We just recovered yesterday from an Exchange database failure. Database was restored and most mail seems to be flowing in and out except for mail sent to a few domains. We have a 2-node DAG (EXCH01 and EXCH02) with the database currently active on EXCH01. All mail flows thru a Barracuda Spam 300 firewall and up until the recovery yesterday all the email flowed fine in both directions. Barracuda has not been touched. Delivery to a few domains is showing as delayed in the queue and is bouncing back with the message:

Diagnostic information for administrators:

Generating server: EXCH01.neweraopt.com
Receiving server: edge.receivingdomain.com (xxx.xx.xx.xxx)

Remote Server at edge.receivingdomain.com (xxx.xx.xx.xxx) returned '400 4.4.7 Message delayed'
11/13/2017 8:29:42 PM - Remote Server at edge.receivingdomain.com (xxx.xx.xx.xxx) returned '451-4.4.0 Primary target IP address responded with: "554-edge2.receivingdomain.com  451 4.4.0 554 Your access to this mail system has been rejected due to the sending MTA's poor reputation. If you believe that this failure is in error, please contact the intended recipient via alternate means.." Attempted failover to alternate host, but that did not succeed. Either there are no alternate hosts, or delivery failed to all alternate hosts. The last endpoint attempted was xxx.xx.xxx.xxx:25'

I have checked out MX records and they seem fine. I have also checked several blacklist sites and our …
I'm trying to set my OWA login option to UPN format. However it seems not to work even though I've set it to that format in authentication. See attached.

I'm trying to use the following format | username@domain.com

Only this format works | domain\username

I've also restarted the IIS.
Few days back any mail related command ( mailx, mail ,mpack  ) stopped working from one sudo id .
in the logs i get error as dsn=5.6.0, stat=Data format error
but this happens with only one sudo ID-sudo1@my_hostname
another id -sudo2 works fine with any of the mail command

sudo su sudo1
mailx -s "Test mail" someone@example < /tmp/test.file
/home/sudo1/dead.letter... Saved message in /home/sudo1/dead.letter
where from=sudo1@my_hostname
message fails to sent

sudo su sudo2
mailx -s "Test mail" someone@example < /tmp/test.file
where from=sudo2@my_hostname
message successfully sent and received.

Not getting why with one prefix it is sent and other fails ... ?
Hello Experts
I have single AD site with 3 domain controllers.
I have 2 Exchange 2016 Servers with CU6 update.
I have just created new DAG and added both servers to the DAG. I am trying to add database copy to second member but receiving the following error

The seeding operation failed. Error: An error occurred while running prerequisite checks. Error: The specified database isn't configured for replication and therefore cannot be used to perform seed operations.

Open in new window

Appreciating any help.
At some point my Gmail account stopped showing all of my emails.  I used to be able to scroll through (or search for) emails from months ago - even if I had several thousand emails since.  Now my Inbox shows my unread emails and just a limit of 50 read emails in the second section.  Where did all my other emails go?  My Outlook still has them all, though sometimes I don't have my Outlook handy.


We are migrating from Exchange 2010 to 2016 and are in a state of coexistence. I'm unable to launch any Exchange 2016 mailboxes from Outlook 2010 and 2016. I am able to open up the Exchange 2016 mailbox from Outlook Web Access. When I try to launch the mailbox from Outlook I get the error "Cannot open your default email folders. Microsoft Exchange is not available. Either there are network problems or the Exchange server is down for maintenance". Any suggestions? I have not cut over autodiscover to Exchange 2016 yet. Is there something I need to configure with Outlook Anywhere for Exchange 2016?
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Which Office 365 licenses permit placing users on litigation hold so that all emails (including emails that have been deleted) will be retained?
I am trying to upgrade exchange 2010 from SP1 to SP3 getting every steps is getting success but when I click on UPGRADE then gets below error.

"The following error was generated when "$error.clear();Install-SchemaExchange -LdapFileName ($roleinstallPath + "Setup\Data\" +$RoleSchemaprefix + "Schema0.ldf""

Please find the attached file for more detail.
Dear Experts, we got an Exchange 2016 server and have an auto mail account, for example: auto@abc.xyz

Dev Team is using this account to sent bulk emails to users via C# code but when they logged into this account in Exchange, there is no any item in Sent item folder. Could you please suggest? Many thanks!
How can I change the default Outlook 2016/Office 365 setting so that any emails sent to the All Employees email distribution group will arrive in the user's Inbox (and not just in the distribution group named "All_employees" below the Groups folder within Outlook 2016? (see the screenshot).

We don't mind if emails sent to this group arrive within this designated folder under the "Groups" folder but need to make sure that these emails sent to these distribution groups also arrive within the individual user's Inboxes.

Is there a setting within Office 365 to set this up?

I have showing in 1  mailbox database in DAG  database size : 1gb       disk space free :76.9%

what does that mean+ what is difference between disk spacesize vs whitespace size?

secondly I am doing patching o my DAG servers , are the below commands correct"? (step wise)

Need to check the what all database mounted in mailbox server.
get-mailboxdatabase –server “mailboxname”

Then need to check the database status. Mounted & healthy.

Then need to check DAG so that which all servers under which DAG.

After getting the DAG info need to move the DBs from restarting server to other server in same DAG.
move-activemailboxdatabase dbNAME -activeonserver destinastionservername

After moving we need check the DB status & then suspend them from restarting server.
suspend mailboxdatabasecopy "DBname"

Once we suspend Need to restart the server.

After restart we need to resume all the database on that server
resume-mailboxdatabasecopy DBname

Then check the DB status.

They should be Healthy in status.

are the above steps correct, any issues I should be aware of?
We have an email system that routes emails to various entities based on the subject.  The account is gmail. We periodically delete emails from the outlook client, but "do not delete emails from server" was selected. We can see them if we log on to gmail via a browser. how do we get those emails back onto the outlook client?  We need to export to CSV and run analytics on how many things went where and when.  There are 13,000 emails so manual isn't an option.

Greetings wise wizards of EE:

I'm helping a friend who has a fairly new iMac, running El Capitan, and Microsoft Office 2016 for Mac. I sent up an IMAP account with his @sbcglobal.net e-mail (from AT&T), which is able to send and receive. However, it constantly prompts him to input his smtp password, and I have confirmed that the smtp settings and port number is correct. I have tried every possible AT&T server settings, and I check "Keep this password in the keychain". He typically inputs his password in the morning, and ignores all requests that appear after (usually several per day) and his email then sends normally. This issue is not preventing him from using his e-mail, but it is highly irritating.

I am convinced it is either a Microsoft application or operating system issue. Both Office & El Capitan are up to date.

Please advice to make this incredibly annoying error message exist no more!

Many thanks in advance,

Hello Experts

I am trying to setup an exchange email account Iphone 7. After providing the email and password, the iphone still asking additionals details like server, username.
I dont have any issue on external Outlook clients
I have created SRV and CNAME DNS records but still facing this issue.

Please advise
Having issues sending and receiving some emails.

Error message below from an email unable to send. (was able to send one email to the address before this happened)

Requested rejected your message to the following email addresses:
To_user (receiving@domain.com)
Your message couldn't be delivered and there was no valid enhanced status code being issued by the remote mail system to determine the exact cause, status: '550 Requested action not taken: mailbox unavailable'.
Requested gave this error:
Requested action not taken: mailbox unavailable

Diagnostic information for administrators:
Generating server: Mail.domain.local
Remote Server returned '550 Requested action not taken: mailbox unavailable'
Original message headers:
Received: from Mail.domain.local ( by Mail.domain.local
 ( with Microsoft SMTP Server (version=TLS1_2,
 cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.1034.26; Fri, 3
 Nov 2017 07:02:05 -0400
Received: from Mail.domain.local ([::1]) by Mail.domain.local ([::1]) with mapi
 id 15.01.1034.026; Fri, 3 Nov 2017 07:02:05 -0400
From: "From_User" <user@domain.com>
To: To_user <receiving@domain.com>
Subject: FW: FAP (Facilitation Alteration permit)
Thread-Topic: FAP (Facilitation Alteration permit)
Thread-Index: AdMNI6GymJLC8EW1QgCae7cDR/f4jQAAFxFQEb9nL4AABx0SAAAdplsA
Date: Fri, 3 Nov 2017 11:02:05 +0000
Message-ID: …
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On monday something changed with my office 365 mail accound and I had focused inbox on my phone.  Prior to that, on outlook 2016 I had the clutter folder.  It was working well.  After Monday I lost clutter in outlook and never got focused inbox.  Its a downgrade.

I had a session with Office 365 support to get outlook to update to a version with focused inbox but to no avail.

My office version is downloaded from office 365.

Any advice as to how to force outlook to update to have the focused inbox.  My Office install is on the Monthly channel.

Thanks and best regards,

Hi Guys,

In MS Exchange 2013, is there a setting that one could archive / restore every single e-mail that is received by the server, for example in a separate archive folder?  Perhaps as a flat file?

For example:  Mails are sometimes deleted by a user or rejected by the system for some reason, and we would like to be able to retrieve those e-mails from somewhere?

Any such options available, or do we have to look at a 3rd party solution?

I’d like to apply Exchange 2013 CU15 to all of my Exchange Server 2013 Standard Edition that is running DAG in three different AD sites (geographically).

This is the settings:

Each of these MBX servers running DAG with Lossless mode.

AD Domain: MyDomain.com

AD Site: Production 1
SITE1MBX1-VM [CAS & Mailbox]
SITE1MBX2-VM [Mailbox]

AD Site: Production 2
SITE2MBX1-VM [CAS & Mailbox]
SITE2MBX2-VM [Mailbox]

AD Site: Production 3
SITE3MBX1-VM [Mailbox]
SITE3MBX2-VM [Mailbox]

So how can I apply the Cumulative Update 15 safely without causing unwanted email flow or Outlook client outage in a 24x7 corporate environment?

After the CU15, I will need to install .NET Fx 4.6.2 to be able to run the CU18.

Thanks in advance.

Currently have an issue where emails are not working and believe its due to the exchange drive being full. It currently has about 400mb free space left. I am trying to see what would be the best way to proceed to get email flow again.  The drive that is almost full is the E:\Program Files\Microsoft\Exchange Server\V14\Mailbox\ directory.  I see alot of log files in this directory but from the research i have done they should not be deleted. Any input is appreciated.

Comcast / IMAP setup.  New Macbook pro

Entire inbox on the Outlook application instance is refreshed…. while working in the inbox reading and replying to e-mails.

From my customer:
"It ‘appears’ that the entire list of e-mails in the Inbox disappears.. And then are all re-downloaded again… without retaining the  flags or categorizations I recently applied to them recently.   I watch the e-mail thumb-nail ID info scroll past on the screen border… sometimes taking several minutes… before I can return to the e-mail item I was working with."
what does DB white space in databases in DAG means in exchange 2010

what should I be mainly concerned with that

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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