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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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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.
This started yesterday around 8am that it was reported we couldn't send or receive any email.  Both inbound, outbound and internal email was no longer working.

I restarted the server a few times and exchange services and found that the Microsoft Exchange Transport service was stuck in a "Starting" state but would never start.  Through research I found some suggestions about renaming the que directory at C:\Program Files\Microsoft\Exchange Server\V14\TransportRoles\data\Queue and allowing exchange to re-create it.  

I found the mail.que file to be around 15gb if I remember correctly.  I was able to kill the process, rename the folder and exchange recreated it and mail started flowing again for awhile then stopped again.  This process was repeated several times as I continued to troubleshoot the issue.

Eventually, after almost 12 hours of suffering with this I ran this script:
Get-MailboxDatabase -Status | Select-Object Name,@{N="DatabaseSize GB";E={"$([math]::round($_.DatabaseSize.Tobytes() /1Gb, 2)) GB"}},AvailableNewMailboxSpace | Sort-Object Name | fl

The result was something similar to this:
Name                     : Mailbox Database ####
DatabaseSize GB          : 539.01 GB
AvailableNewMailboxSpace : 21 mb

Interestingly it's odd to me that the databasezize in GB is 540 (and doesn't seem to ever grow).  The drive exchange resides on has 383GB free space.

Anyway, I watched this for awhile and saw the availablenewmailboxspace continue to shrink and …
We've got a Linux server which has been running as a mail server (Sendmail) for years

DNS listings for SPF, DKIM, DMARC and ADSP has been in use for the past 3 months with no issues.

For DKIM we're using OpenDKIM and two days ago we've installed OpenDMARC and are still in the testing phase (We're not sending reports at this time)


For the life of me I can't figure out what I'm missing

I'm trying to figure out how to get Sendmail via OpenDMARC to follow an established policy of a received email by Rejecting or quarantining a email (as specified) if the message alignment fails .
User can’t remember Gmail password BUT has the account working on a laptop

Eventually that laptop will die

Is it possible to add a forward all email to another address in the mean time to be covered for that eventuality ?

* totally impossible to retrieve password - we have tried everything !

Forward possible to a new gmail account and we will store password this time - it’s  possible ? Without knowing password ?

Thanks !
1.pngso all of a sudden some emails stop flowing and my connector is not validating, been setup for years and we did not change any server or network settings

i have Office 365 and a hybrid server - exchange 2010

the emails that are failing are coming from my mercury server and flows thru my exchange to office 365. i have contacted microsoft support but they are saying its an internal issue.
Hi guys,

I got a pop3 email in mac outlook. I want to transfer all emails to a office365 outlook profile in my Mac computer. I recently migrated from pop3 to office365. So doing this transfer to have my old emails in office365.

So in outlook, I got both profiles now. Old pop3 email and office365 Email. I can drag and drop each folder email. But there are many sub folders in inbox, which will
Be difficult to crate all folders in new office365 inbox and then doing drag and drop each folder.

Is there any other way to do it in a better way.
Guys I am having a significant problem I recently change my email password in Gmail know I forgot the password and the recovery email account I don’t have access. How can I recover my account?
I can't seem to get any exchange mail on my iphone X.  We're running on premises Exchange 2010.  When I add the account on my iphone, I choose exchange and enter in all the details.  It passes, I get all "checkmarks", but no mail will load.  Folders won't even load.   Any ideas?  Btw, this very phone had email working just yesterday, but I decided to reset to factory and start from scratch.
Configure Exchange 2013  autodiscover and Web Services

I would like to know if I will have to configure Autodiscover  URL on each CAS server or just one of the CAS servers.
I also want to know if other Web services URLS such  ECP,OWA,OAB,ACTIVESYNC,OutlookAnyWhere,etc.... will have to be configured on each CAS Server

Thank you.
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Hello Experts - I'm trying to find a free or inexpensive service that would allow me to send a fake phishing email to my staff to find out how many of them are clicking on links they shouldn't.  It would ideally include a list of people who clicked on the link and perhaps entered data on the site it takes them too.  If I could get an idea of how many staff are ignoring my all too frequent email warnings and training sessions I could more easily target the offenders with additional training.
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
Dear Experts

I need some help please. I need to gather incoming and outgoing email statistics per day for an Exchange 2010 server? Any advice?

The most important thing is the total size of all incoming and outgoing per daily basis.
our internal IT security policy is currently out for review. One of the key points in the email section of the policy is that users should not include personal information in email subjects/titles. My query is "why not". If its internal traffic between employees, why would there be any more of a risk of the personal / sensitive info being in a subject, above and beyond it being in the body of the text or an attachments, why specifically could you think that the subject field in particular should be avoid of any personal or sensitive information? I was wondering if its because that gets captured in email track logs whereas the body or attachments do not - but I thought I would see if anyone else could think of any logic behind it before I query the thought process behind that policy requirements.
when sending email from inote (lotus webmail),
error: could not open id file
able to read emails
notes client do not have any issue.
Domino version: 9.0.1
browser: ie or edge
not a new user.
i am getting following error while sending email to 1 particular user.

550 DKIM Sender Invalid - envelope rejected

554 5.0.0 Service unavailable

all other emails are going through

is it the recipient server is having some issues
I've recently enabled SPF/DKIM/DMARC for our email system.  My understanding is that this will help fight email spoofing?

But what about other malicious email events?  How do I thwart email virus and attacks coming from sites that are not spoofing?
I hv a readonly account & but unfamiliar with navigating in O365 Exchg online.
My security vendor would like to know 2 information about our O365  Exchange online:

a) what's the highest number of emails a top recipient can receive during peak hour
    per hour

b) what the average number of email attachments we receive each week

Can guide me where/how to get the above info
Hello fellow Experts Exchange members:

I have a confounding problem with one user who has Office Home & Business 2016 installed on a domain-joined laptop that is often used to connect from outside the office using VPN.

(This is not occurring with any other user.)

I had to recreate the user's Outlook profile this morning due to an unrelated issue.  When attempting to reconnect the user's Outlook to the on-premise Exchange 2013 server, the autoconfiguration process appeared to behave normally.

However, upon opening Outlook, the user's e-mail address was incorrect.  In fact, the e-mail address was not even for the same e-mail domain - e.g. @Company.com.

Somehow, Outlook on the user's laptop had configured itself with an "outlook_[long series of numbers and letters]@outlook.com" e-mail address.

The user's previous e-mails were not in the Inbox or Sent Items folders, and none of the user's previously-created subfolders appeared.  Also, there were no contacts or calendar items.

When I tried to send a message, the message sent successfully, but the resulting e-mail appeared with the outlook_@outlook.com e-mail address instead of the correct user@company.com e-mail address.

I tried logging in at Outlook.com with the user's user@company.com e-mail address and password was able to log in.

However, I also tried logging in at the Outlook Web Access (OWA) page for the on-premise Exchange 2013 server and was also able to log in using the user's user@company.com …
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I need to update the SSL Cert in my Exchange 2013 environment (2 MB servers, 2 CAS servers, 1 MB+CAS server).  The existing explicitly named cert expires in 2 weeks.  I want to update it to a different, already existing wildcard cert that we use for other servers.  (eg - existing cert is mail.domainname.com.  New cert is *.domainname.com)

So my question is, what is the process for installing this existing wildcard cert to my Exchange environment since I don't need to "renew" or create a CSR...I already have the cert.

Thanks in advance.
got office 365 email in a 2013 professinal plus outlook. everything works fine.
but when i search for few particular emails, it shows results for last 3 months. and it does show anything for one year, and shows rest emails after a year. am not sure why it is not showing one year of emails if i search ??
but if i scroll down i can see all emails and from web portal, if i search its showing up all emails.
problem is only in outlook. its not showing emails for one year when i search. i tried indexing, new profile. but still same issue.
any could help with this ??
i have attached a screenshot to show the time gap. its not showing for one year.
My Exchange VSS admin writer is missing for some case.  I just discovered why my harddrive was filling up so quickly, because none of the logs have been truncated since February of this year.

I've tried different registry changes, but nothing worked, I searched online and everything I tried didn't work, so short of calling MS I'm hoping someone has experienced this and knows how to solve it?

My issue is that I am using Arcserve to backup my server, and its backing up exchange, but it's not truncating the logs, then I used windows backup server, and it ran successfully, but again, it didn't truncate the logs.


log filesvssadminlistwriters
Windows 2008
Exchange 2010
Able to access email from outlook clients
Able to access email from web using mail.company.com/owa
suddenly all the smartphones can not access email from their phones.
Any ideas as to where i can look for the culprit and what i can do rectify the issue?
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.

Hi guys

On the weekend, our Exchange 2010 server stopped receiving emails because the C drive was below the accepted threshold. We also use Messagelabs to route any inbound emails and outbound emails.

Once I resolved the issue today and got the C drive above capacity again, emails started trickling through. However, we are still getting emails coming through from Saturday evening.

My question is: Is this down to the original sender and how often their email system tries to resend the original email? (i.e. beyond our countrol?)

Thanks for helping

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.