Questions tagged [email]
The server configuration of email, including POP3, SMTP, IMAP, and popular server software packages that control email.
6,634
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What is meant by "Message sorting optimization records" in dovecot index?
Dovecot documentation here "https://doc.dovecot.org/developer_manual/design/indexes/index_file_format/#main-index" says that "Message sorting optimization records" are stored in ...
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What is difference between uidvalidity and list index file in dovecot?
Dovecot's document notation says that uid-validity file store IMAP UID to filename mapping but it also says list.index file also store same. If it's so what is need of two files.
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In postfix can I mention sender access map in client restriction?
It's a question out of curiosity rather than necessity. What should happen say I place sender access map inside smtpd_client_restrictions and also place client access map in smtpd_sender_restrictions ...
- 175
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In postfix how parent_domain_matches_subdomains helps rejecting mail for subdomains?
Based on the standard configuration given in https://www.postfix.org/STANDARD_CONFIGURATION_README.html#firewall the parent_domain_matches_subdomains = debug_peer_list, smtpd_access_maps should help ...
- 175
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How OpenDKIM decides which emails to sign?
In OpenDKIM, what domain does it consider to use when comparing to internal hosts? Do it consider the domain of Return-Path (i.e. envelope MAIL FROM's domain) or header From or HELO's domain.
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Why is it advised to disable relayhost when hosting mail server behind firewall?
I am trying to setup an MTA. While reading documentation I came across "Standard Configuration" for Running Postfix behind a firewall.
I am confused on this part:
IMPORTANT: do not specify ...
- 175
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35
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Can I log when the message arrival rate exceeds the message delivery rate in postfix?
I am trying to implement a MTA, on reading documentation of the postfix I found a parameter 'in_flow_delay' whose description in sort says 'Time to pause before accepting a new message, when the ...
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What is behaviour of opendkim while verifying an email with multiple dkim signatures?
I am trying to implement DKIM verification using Opendkim and postfix. The doubt I am struck by is what will happen if the email has more than one DKIM signature and one of them fails (as like failed ...
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What are typically the headers which I should oversign?
I am trying to setup MTA using Postfix and using opendkim for dkim signing. When I went through opemdkim documentation it have a field which is named 'OversignHeaders' document describes it as: "...
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sendmail setup and config
I am trying to figure out how to setup sendmail to allow for mail to be sent between two machines. In my case here's what I did.
Installed sendmail
commented the line where sendmail was servicing ...
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What does "--[no]subdomains" option in opendkim-genkey mean?
Based on the documentation --nosubdomains "Disallows subdomain signing by this key". But didn't we need to create separate DKIM records for subdomains regardless?
Please correct me if I am ...
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225
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What is difference between using smtp vs relay transport type in postfix?
I am trying to setup MTA which should submit different intranet mail gateways based on the recipient's domain. For that I thinks transport_maps in postfix should be setup for selective domains; if ...
- 175
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How to restrict based on combined usage of sender email and client ip address in postfix?
I have a MTA (postfix) with sasl implemented. I want that for a subset of users I can map their email address to a particular range of ips (separate for each email user). If a user tries to send email ...
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How to bypass postfix milters for certain users?
I am trying to setup an incoming MTA server using postfix. I have specific requirements that emails for some of the users should not go through the milters. Is there any way this can be done in ...
- 175
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Too many connect from unknown postfix
I am trying to set up an incoming email server by using postfix as MTA the issue I am facing is that there are too many 'connect from unknown' lines in the log. Can anyone help can I debug this issue? ...
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OpenDKIM gets installed without RSA-SHA256 support
I compiled opendkim from source with the following commands:
mkdir /opt/opendkim
cd /opt/opendkim
wget https://sourceforge.net/projects/opendkim/files/opendkim-2.10.3.tar.gz
tar -xzvf opendkim-2.10.3....
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Spam filters: IP address with no history v. good history [closed]
Zoho gave me an IP address with no history this week. Senderscore.org says there's insufficient data to evaluate it. At other times Zoho has assigned me an email sending IP with a fair or good score.
...
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Is it possible to forward messages to a Microsoft 365 mailbox with the same e-mail address?
My organization has adopted Microsoft 365 for cloud services except e-mail, which is still managed on-premise. As my M365 account coincides with my e-mail address, now the same address refers to two ...
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Perm Error sometimes not know if it sender issue or receiver issue
I am facing the problem, sometimes from the sender , i am able to receive the mail, sometimes it block, getting the error ---
Sender: @dekra.com
Recipient: @autodienst-hoppegarten.de
working header: ...
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74
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Configure postfix virtual transport to deliver mail to arbitrary (local) addresses
I'm using Postfix in a very niche application with no inbound or outbound SMTP connectivity (other than via the loopback interface).
I would like to configure the postfix virtual transport to deliver ...
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PHP mail.add_x_header not showing in log
On Ubuntu 22.04 I have the following in /etc/php/8.1/apache2/php.ini (and have restarted Apache), and in /etc/php/8.1/cli/php.ini:
; Add X-PHP-Originating-Script: that will include uid of the script ...
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SPF & DMARC: One data center won't propagate
I'd like to have email deliverability so I can gather and nurture business leads. This involves Sender Policy Framework and DMARC. Neither is working.
I'm using Bluehost. I had DMARC right, lost it in ...
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157
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What are the correct settings to enable TLS between Postfix and Dovecot via LMTP?
I am trying to get Postfix to forward mail via LMTP to Dovecot. This works fine when TLS is turned off in the settings on both sides.
Once TLS settings are enabled, Postfix connects via LMTP and ...
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635
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SPF record in DNS sending via Gmail
I have an old domain that I want to re-purposes for a new website which will send emails. I'm using Asp.Net Core, if that makes a difference (I do not think it does). I've written several apps that ...
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Cannot send e-mail to one account on server
I am responsible for administering a web and mail server which has a number of users with mailboxes which function correctly. I recently added another user as I wanted to set up a separate e-mail ...
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54
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Does LMTP support authentication?
Scenario:
A Postfix Server runs on a VPS with a hosting company.
A Dovecot IMAP server runs inside the office.
We want Postfix to push mail it receives to the Dovecot IMAP server, using the least ...
- 117
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Add the name of the file analyzed to the e-mail (logcheck)
I use logcheck to receive apache logs. My question is how to configure logcheck to add the name of the file that is analysed in the email. Example: at the moment I have this:
This email is sent by ...
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70
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Postfix seems to be running and listening on the public network interface, but external clients cannot connect?
I'm setting up a new Postifx server on Debian 12. I've installed the Debian package and confirmed that Postfix is running, and is listening on ports 25,465, and 587.
Postfix is running and there are ...
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Conditionally forwarding incoming mail to a different address
I have a task at hand that would involve grabbing incoming mail from an IMAPS server (Google Workspace), and then redirecting it to another address (for ingesting attachments from emails).
Sadly, I ...
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Mail client fails through TOR SOCKS5 proxy with authentication failure
Happening for all POP, IMAP & SMTP protocols with or without SSL.
* Account '***': Connecting to POP3 server: ***:110...
[DATE TIME] POP< +OK Dovecot ready.
[DATE TIME] POP> USER ***
[DATE ...
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Postfix+Dovecot: filter email with certain `To:` address
I have a postfix+dovecot email server. There is one mailbox that was used by the Procurement department in many online shops and the address got disclosed and included in a spam list.
I would like to ...
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158
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Sendmail unable to email to specific domain
I have a server running Sendmail and is able to email to all domains except my company's email (company1.com). I have tested to sending to gmail and other email providers with no issues. Sendmail is ...
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A Non-MX mail server + Google Workspace, is this viable?
I have a domain (example.com) configured for sending and receiving mail using Google Workspace. I need to launch additionally a separate (own) mail server. Switching completely to the new server is ...
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140
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Should HELO, MAILFROM and From use the same domain?
I configured a mail server a couple of times before and I believe back then I thought
that the answer is "yes."
But I'm about to configure another one, and it seems that I was wrong. Let's ...
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Postfix : change email from unix_user@domain to a something@domain
I have two domains on a server, they are rarely used and they have 2 ubuntu users like
domain1_user
domain2_user
and I want to associate email addresses like
info@domain1
info@domain2
Obviously I ...
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82
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How to properly filter emails through EXIM system filter?
My server recently encountered a large volume of incoming spam messages. For each message, Exim agent generated a message with the following content for the sender:
"Mail Delivery Failed: ...
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DKIM Signature Body Hash Verified to Office 365
I am checking the email header in https://mxtoolbox.com and getting the error DKIM Signature Body Hash Verified. Problem only occurs when sending emails to other Office 365 accounts. The same email ...
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How to make postfix sign non-delivery notifications with DKIM?
I have set up my "postfix" server to sign outgoing messages with DKIM and verified that it works correctly for SMTP users using authentication. However, "non-delivery notifications"...
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Why are emails to Microsoft (e.g. Hotmail and Outlook) never being received?
I have a form on a WordPress website that, when submitted, sends an email to 4 email addresses. The two gmail.com addresses receive the email. The hotmail.com address and a domain hosted with MS ...
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70
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Postfix - Forward mail externally through relay
I manage the mail server for mydomain.com. Some users have a local IMAP mailbox, but for some their address is an alias and I'd like to forward their message to their external address. I've configured ...
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Wrap plain text mail in html
we use Postfix as MTA to send our mails from our system. Unfortunately we have an old persistent system which we cannot change, which sends mails to our customers in plain text format. I would like to ...
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Should I create a new forest for the DMZ
I have a local area network with a DC called "mycompanyptyltd.local" and a DMZ that is not in the AD DC forest.
I own the domain "mycompany.com" and I receive and send email from ...
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405
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Google claiming my server is sending SPAM
My email server serves only a few people who are all known to me. I recently forwarded an email from my server to my own GMail account but got this error on my servers mailq.
relay=alt1.gmail-smtp-in....
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Simple solution to archive dovecot/postfix emails to second server nightly for long term storage with roundcube access
Our email server has ~150 email accounts containing material that cannot be deleted for 10 years. Some accounts are heading towards 10gb of data so I'd like to setup a nightly archive process that ...
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`mail` shows a message hard to identify the source of
Here's me running mail command in a CentOS 7 server:
[root@ ~]# mail
Heirloom Mail version [version no.]. Type ? for help.
"/var/spool/mail/root": 2 messages
> 1 (Cron Daemon) [...
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can't get email from exchange to postfix
I configured a postfix mail server to receive emails.
I enable TLS as per security requirements as well as port 25 is banned by the provider.
I enabled both 465 and 587 with the following on master.cf
...
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105
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MS365: Sending encrypted to remote tenants occasionally fails with "user not in tenant"
We are attempting to replace a secure email gateway solution with MS365's inbuilt email message encryption.
We have a mail flow rule set up to force encryption from a specific sending address to any ...
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Delaying dictionary attacks in exim
I have ongoing attacks against my exim server.
I'm trying to delay the attempts with the following acl
deny condition = ${if and {\
{>{$rcpt_count}{10}}\
...
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221
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Where does the new Outlook store signatures?
I know that the old (Office 2021 and earlier) Outlook client stored signatures in %AppData%\Microsoft\Signatures.
Where does the new (post-2023) Outlook desktop client store its signature files?
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Sign-Up verification emails going to spam despite proper authentication
I am using SendGrid to relay emails sent via Drupal. I am struggling with Gmail specifically marking Sign-Up verification emails as spam despite using DKIM, DMARC, SPF, reverse DNS, everything there ...
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