All Questions
155
questions
0
votes
1
answer
192
views
How to improve sender score for personal mail server
Background:
I have an own domain and an own mail server that sends out the mail for this domain. The users are only my family so there are less than 10 users with probably 20 mails sent per day.
...
- 1,013
-1
votes
1
answer
2k
views
How to fix spam listing of IP due to SMTP HELO banner
Spamhaus has listed my IP a few times for an apparent problem. They are indicating:
A device using <ipv6 addr> is infected with malware and is emitting spam.
<ipv6 addr> is making SMTP ...
- 169
2
votes
2
answers
1k
views
What exactly can I conclude from "High scoring spam message has been dropped (in reply to end of DATA command)"?
I operate a web site that offers user registrations. Users get automatic registration success e-mails, sent through a professional e-mail hosting company (not directly from our own server). This has ...
- 153
1
vote
1
answer
76
views
Outbound email restriction
We have a project to set up around 5,000 plus email IDs for an educational institution. Emails are meant mostly for receiving mails, and the instituition wants to set up some rule that no email id can ...
- 685
0
votes
1
answer
370
views
How to stop spammer spoofing my domain for emails
I've scanned all my code and even changed the passwords to my google apps account such that the SMTP password has changed. However, spammers are still sending emails from June24-eBay-USA-contactmsg-...
- 302
0
votes
2
answers
495
views
Configure Postfix external relay for UCEPROTECTL3 rejection
Is it possible to configure MTA Postfix server to bypass UCEPROTECTL3 rejection ?
Example when my server connect to recipient server then I get information:
Diagnostic-Code: smtp; 554 5.7.1 You are ...
- 51
0
votes
0
answers
18
views
My postfix is used for spamming [duplicate]
I need your help.
My postfix is sending spam mails.
I checked my main.cf and it should be fine.
In the following a snippet of my mail.log
Jan 3 22:35:41 mail postfix/pickup[104179]: 866352963F01: uid=...
- 1
2
votes
0
answers
101
views
Exim: Redirect mails without spooling
I am running a personal mail server using exim that only forwards mails (and also runs a few mailman mailing lists).
Unfortunately, my server’s spam protection is worse than that of the mail provider ...
- 4,049
0
votes
1
answer
737
views
Provider for outgoing mail from own Postfix server
I've been running Postfix on my own dedicated server (hosted by Hetzner) for years, however, it's getting increasingly difficult get outgoing mail to Outlook/Hotmail and sometimes Google delivered. ...
- 145
1
vote
0
answers
546
views
Yahoo Mail server constantly deferring mail from my server "due to user complaints"
I have a 100% no-spam score on mail tester.
Have no problem with Gmail server, all users getting my emails.
Have everything like SPF and other spam related criteria enabled.
Yet, Yahoo mail server ...
- 111
0
votes
2
answers
2k
views
How to REJECT email using SpamAssassin
Is it possible to reject emails, like it is done in Postfix using header_checks, using SpamAssassin? Normally, the SpamAssassin only adds the spam flags and by default adds the word SPAM in the ...
- 179
2
votes
2
answers
8k
views
How to read this DMARC report? Why does Yahoo still reject mails from my server?
I've got hMailServer set up on my server, which bulks-mails a newsletter to an opt-in subscriber base. I have set up DKIM signing, a SPF record explicitly giving my server permission to send email on ...
- 273
-3
votes
1
answer
146
views
Does anti spam software block IP addresses of large smtp providers? [closed]
Does anti spam software routinely block IP addresses of large smtp providers such as Mailchimp or SalesHandy?
- 133
0
votes
0
answers
40
views
What email headers are useful for determining if my email account has been compromised?
I've recently received a lot of spam replies (automated replies from users, and rejections from mail servers) to a certain email address. I've taken the obvious precautions of changing passwords, and ...
- 365
0
votes
1
answer
216
views
Best way to restrict/manage PHP apps to use my postfix?
I want to allow PHP apps to send mail but under very restricted conditions.
And I don't want to allow sendmail-like command for PHP apps (I'm using chrooted PHP and it's too much headache), thus I ...
- 597
1
vote
1
answer
407
views
Is Office 365 Exchange capable of SMTP connection-stage rejection?
Microsoft Office 365 Top senders and recipients report shows that 15-20 % of messages in the tenant are from [email protected] i.e. Office 365 Exchange sends a lot of Non-Delivery Notifications (...
- 50.2k
0
votes
1
answer
5k
views
EXIM SMTP allows to send mails without login / authentication via telnet to any domain
I'm ashamed, but I have to ask for help. My server is being used for sending spam, I've found out I can simply connect with telnet (edit: from any server in office, home and even directly from CMD/...
- 1
0
votes
0
answers
101
views
Avoiding E-Mail spam filters (possibly based on originating computer?)
We recently started to send out a higher amount of E-Mails (invitations to a private event) to a select number of people.
Now from some of those people using office365 for Mails, we were informed that ...
0
votes
0
answers
36
views
Do some smtp servers refuse to SEND to a spam-blacklisted host?
Is it known that some mail admins or mail programs setup their server like this? Is this a small minority? I don't have any examples, but i'm just curious.
- 109
0
votes
0
answers
278
views
Identifying suspicious outgoing SMTP connections (a.k.a. spam) after CBL listing
The IP of my email server has been listed on Spamhaus CBL, which states that the server "attempted to send email without using the HELO/EHLO command", "[which] is generally indicative of a broken ...
- 1,265
1
vote
1
answer
291
views
Mail Server allow sending spam to hosted mailboxes
I got an issue on both of my servers (Postfix + Dovecot and one on Zimbra)
My issue is some robots send spam without login to our hosted mailboxes using the same FROM/RCPT.
It seems Google got the ...
- 297
0
votes
1
answer
1k
views
How to pevent unwanted SMTP connections EXIM
I have a VPS configured to use PHP to send out periodical alerts via email (sendmail) where I connect via SMTP to a google apps email account. The server is using EXIM as the transfer agent.
In the ...
- 105
0
votes
0
answers
496
views
Spam from my Debian Stretch server - postfix
I have a huge problem with my Debian Stretch installation. Out of the blue one client email address started sending a huge amounts o spam.
My server uses standard configuration. I installed it with
...
- 13
13
votes
2
answers
4k
views
Detect spammers on my server
I recently got one Undelivered Mail Returned to Sender while sending my newsletter to one of my 1500 customers. My website uses a double-opt-in procedure to make sure, the user explicitly want to ...
- 271
1
vote
2
answers
5k
views
All outgoing mail is marked as spam by gmail [duplicate]
All my emails sent from my SMTP server (created with VespaCP) is being marked as spam by gmail. DNS and DKIM is setup correctly. By using isnotspam.com, I have figured out that the reason is ...
- 121
0
votes
1
answer
431
views
Got an Abuse email for spam from my server, but postfix logs don't show them [duplicate]
We have a server with 300+ websites on it, and it has gotten an abuse letter from spamcop. We have investigated the logs, and searched for the PHPMailer version stated in the mail and all came up with ...
- 181
3
votes
1
answer
760
views
Need help determining origin of spam email
As a quick background we have spam that is being sent out with our domain name. As a result we have added SPF record to our domain DNS, now obviously this will assist in making sure this spam is not ...
-2
votes
0
answers
38
views
Whitelist SMTP after hacking? [duplicate]
My Wordpress (hosted on GoDaddy) was hacked via SQL injection a few months ago. I hired a consultant to help me clean out WP and the site is functioning back to normal. Unfortunately, as part of the ...
- 289
1
vote
0
answers
1k
views
Most received mails are marked as spam
I use Google Mail for all my personal mails.
I use a custom mail address which is configured to forward all mails to my Google Mail account.
When sending mails I use the feature to use another smtp ...
- 193
2
votes
2
answers
103
views
why can the Sender field not be easily configured?
To clarify this and this explanation for Sender::
In brief, From: in the message indicates the mailbox of whoever wrote
the message, Sender: indicates the entity which sent a message on
behalf ...
- 229
4
votes
1
answer
4k
views
SpamAssassin sendmail permission denied with Postfix
My server worked, but I installed SpamAssassin using a tutorial from Digital Ocean.
Here is my /etc/default/spamassassin:
# /etc/default/spamassassin
# Duncan Findlay
# WARNING: please read README....
- 55
1
vote
1
answer
546
views
SPF, DomainKeys and DKIM for alternate domain authenticaton
Lets say my domain is example.com and we have SPF records for the SMTP servers on example.com. Now lets say I have decided I want to allow example.org to send mail as example.com.I know how to add ...
- 649
0
votes
1
answer
292
views
email backscatter returns not seen on mail server
We have a user email that we think is under an backscatter attack. We can find no evidence of the account being compromised. The user also states they have not sent out any of the emails they are ...
- 649
0
votes
2
answers
362
views
E-Mail delivery mechanism
Background
I am working with email headers for spam detection.Each E-Mail header contains many "Received-from" fields,each "Received From" field added by an intermediate Smtp/Mail server in the path ...
0
votes
1
answer
305
views
Spam sent from my dedicated server Centos/Postfix, no idea on how to block people from connecting
I've been reading a lot of topics here for the last 2 hours, made some change and yet I'm not sure how things happened and if things are fixed.
First, this morning, I received an email from OVH, ...
- 153
0
votes
2
answers
164
views
Postfix Catchall - Avoid Spam
I've 2 accounts on my CentOS server configured with catchall email accounts. Lately I've been receiving bounced emails with virus that were supposedly sent from my server account, Ex: somestragename@...
- 479
0
votes
1
answer
348
views
Mail Server allow sending spam to own domain
I am having trouble configuring my mail server (Dovecot and Postfix). The problem is that someone can send spam mails to my address from my own mail server. The server is not open-relay but it seems ...
user2521471
0
votes
1
answer
4k
views
Exchange server 2016 Content Filtering
I have setup an exchange server on premise with at SMTP Relay on our VPS. It works very well, unfortunately I’m a little confused as to where I setup the various permissions for SPAM.
All my incoming ...
- 38
0
votes
0
answers
208
views
mail server should anyone be able to send internal mails from external IP without authentication?
Sorry for the long title.
My parent organisation that owns the company I work for accepts emails to be sent from [email protected] to [email protected] when connecting via port 25 telnet externally. I'm ...
- 293
-1
votes
2
answers
2k
views
How can I reject spam before reaching SMTP on Postfix
My server has started receiving thousands of attempts to use my mail server to send spam from dynamic.hinet.net. The attempts are always rejected, but it's non-stop. I'd like to block these attempts ...
- 109
-1
votes
1
answer
492
views
Add a second IP to SPF record, from an external SMTP server [closed]
I would like to add the IP of an external SMTP server to an existing SPF record, which is looks like this:
"v=spf1 a mx ip4:185.6.139.6 a:frey.mailpool.1.netmask.hu a:frey.mailpool.2.netmask.hu a:...
3
votes
0
answers
2k
views
Outlook.com rejects: 550 SC-001 (BAY004-MC5F13)
I am operating a cluster of 3 dedicated machines for a webapp, each of those uses sendmail as MTA. Hostnames are node1.domain.com node2.domain.com node3.domain.com
Unfortunatelly outlook.com rejects ...
- 2,192
1
vote
3
answers
1k
views
How can I find out which script/program/user invokes exim (and is sending spam)?
The problem
A client of mine asked me to take a look at his shared-hosting webserver for the following problem, but I'm stuck at finding out what's wrong. His server is being blacklisted by a lot of ...
- 163
0
votes
1
answer
685
views
How to Stop Exchange Server 2003 sending out Mass Spam / Virus Email from Unkown Account?
I'm young and new to the scene, I have been working on a family member's business server. It is an old server and has a few problems but has
a big main one I'm trying to fix now.
I'll try be as clean ...
-1
votes
1
answer
2k
views
Exchange 2013 Receive Connector Scoping and Open Relay
I have an Exchange 2013 server which was a victim of spam infiltration, and the exchange server was being used as an open relay for unauthorized users (and domains) to remotely send spam. I have done ...
- 13
4
votes
2
answers
989
views
Postfix seems to send spam
I recently discovered this in my postfix-log:
Aug 4 11:09:12 mail postfix/smtpd[71597]: connect from unknown[59.88.35.206]
Aug 4 11:09:14 mail postfix/smtpd[71597]: Anonymous TLS connection ...
- 43
6
votes
1
answer
167
views
How Does Low Volume Affect (esp. live.com) Email Deliverability?
I've been sending emails for years with out any serious reputational shocks, but with low IP volumes (no bulk mail or automated transactional email), even with multiple Domain names.
My Gmail ...
- 161
0
votes
1
answer
386
views
Forward all SMTP traffic to anti-spam server except for authenticated SMTP?
Historically, we have handled SMTP traffic across a handful of multipurpose servers each with their own local spam-fighting stack. We've grown and this is no longer feasible to maintain. Now we have a ...
- 648
8
votes
2
answers
17k
views
Is setting up my own SMTP server to send email a waste of time with regards to deliverability?
I have a dedicated host serving a few domains I manage. I host my own email and IMAP server.
The server is at buildoneforme.com with IP address 144.76.81.247. I think reverse DNS is working:
$ host ...
- 233
10
votes
1
answer
7k
views
Postfix reject_unknown_reverse_client_hostname: replace default unknown_client_reject_code (450) to 550. Why/When I should not?
In the daily battle against SPAM, there have been several times when I've been tempted to heavily enforce DNS requirements from clients connecting from the wild Internet.
In detail, I would have added ...
- 4,178