Questions tagged [spam-filter]
The spam-filter tag has no usage guidance.
187
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99
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How to send emails and avoid them being classified as spam?
This is a canonical question about how to handle email sent from your server being misclassified as spam. For additional information you may find these similar questions helpful:
Best ...
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4
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Best Practices for preventing you from looking like a spammer [duplicate]
I'd like to feel more confident setting up mail for my clients with regards to false positives. Here's what I know:
SPF records are good, but not every spam filter service/software (SFSS) uses them.
...
- 14k
10
votes
2
answers
9k
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Recommended way to implement Postfix 'before-queue' SpamAssassin filtering?
After some discussions with colleagues and the relevant depts. in my office, I have come to the conclusion that for my Postfix server, I must implement a before-queue filtering. The reason is that ...
- 5,148
10
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3
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How to edit bad word filter in SpamAssassin?
How can I add several custom "bad" words into SpamAssassin, so emails that contains that words are marked as a spam?
UPDATE
one of the keys is to edit file /etc/mail/spamassassin, and to add badword ...
- 863
10
votes
1
answer
4k
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How to configure amavisd-new for only scanning on particular senders/servers?
I'd like to know how to configure amavisd-new to only scan for Spam on particular clients (IPs, CIDRs or hostnames) or alternatively sender's email domain.
I know that it is possible to do it on a ...
- 17.2k
8
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2
answers
14k
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Optimal parameters set for Postfix "smtpd_recipient_restrictions"
we've inherited the DNS from another ISP and now our mail server is bombed by about 1000 emails per minute, 99.99% of these emails are just spam. We're trying to optimize the filtering/rejecting the ...
- 193
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votes
2
answers
5k
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GMail suspects confirmation email in stealing personal information
When user registers on my web site, web site sends user email confirmation link.
Subject:
Please confirm your email address
Body:Please open this link in your browser to confirm your email address:
...
- 331
6
votes
2
answers
7k
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Postfix: content-filter vs. milter
I have a Postfix mailserver with content filtering using AMaViS via the "content-filter" option of Postfix. Now I wonder whether it would be better to use AMaViS as a milter instead of the contet-...
- 889
6
votes
4
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What is DNS TXT record "mailru-verification"?
Sometimes I see this mailru-verification DNS record.
I've Googled - and Yandexed ;) - but I found nothing about it.
I suspected that is a kind of russian SPF implementation...
dig example.com TXT
...
- 529
5
votes
3
answers
1k
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97% of emails reaching IronPort/Domino are Spam
We have a Domino mail server protected by Iron Port (v7.1.5 I think). Iron Port reports an average 96%-97% of emails are stopped by reputation filtering, and around 3% of emails are clean messages.
...
- 365
5
votes
1
answer
14k
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Improve Spam Confidence Level (SCL) for outgoing emails
I have a postfix SMTP server on Ubuntu. I have valid SPF and DKIM records, as verified by the email header my customer received.
Authentication-Results: spf=pass (sender IP is XXX.XXX.XXX.XXX)
...
- 1,041
5
votes
2
answers
15k
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Spam passing postfix config "hostname does not resolve to address: No address associated with hostname"
On a postfix MTA MX setup, I have a spam mail pass two checks which it definitely shouldn't.
The postfix/smtpd process logs these warnings, which should be a hard fail in this setup:
hostname * does ...
- 359
5
votes
3
answers
7k
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Why does gmail flag my server emails as spam?
I recently moved my server to a new slice at slicehost and since, gmail has been flagging my email as spam. I have added domain keys, created a SPF record, have reverse dns setup, and my ip is not ...
- 193
5
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3
answers
2k
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How to modify a message, so it will be for 100% recognizable as spam by Exchange junk e-mail filter
I have an sendmail server, sitting in front of my Exchange server. This server filters spam with SpamAssassin (and does it incredibly well!), but it merely tags spam messages with appropriate header ...
- 501
4
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3
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Do mail servers and/or spam filters care about a domain's root A record?
I have a domain which I only use for email adresses. I don't host any content there.
My provider added an initial A record at the root of my domain which points to a server that delivers a ...
- 424
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5
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3k
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How to configure email server to send lots of transactional emails
My organization is currently outsourcing email delivery to an SMTP service provider. We're considering bringing that back in house to deliver our own emails.
We send about 5k transaction emails per ...
- 143
4
votes
1
answer
6k
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Is there any way to prevent Excel 2007/2010 from including .bin files in saved .xlsx files?
In case anyone isn't aware, the new Office 2007/2010 files are actually a type of archive file.
Since deploying some recent (ish) Microsoft updates to our client machines, we've been getting lots of ...
- 54k
4
votes
2
answers
2k
views
Barracuda tagging email with 'date grossly in the future.'
I have a Barracuda 300. Granted it's running on some old firmware and the Energize updates are quite outdated. I'd like to update them, but, not my financial decision to do so.
Starting around the ...
- 173
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4
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15k
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Message Queue building on Barracuda Spam Firewall
I have just installed our new Spam Firewall, and all seemed well. But the Spam Firewall has now decided to put all mail in a message queue and I have no idea how to force it on or anything as there ...
- 567
3
votes
4
answers
500
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Hosted Anti-Spam Service vs. Anti-Spam Appliance
We're currently using Content Catcher, a hosted spam solution. For less than what we pay them per year, we could purchase an anti-spam appliance to run in house. From a simple dollar perspective, it ...
- 522
3
votes
8
answers
4k
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Block spam by using geoip filter?
We are looking for a way to be able to block spam based on geographic location by filtering using geoip.
context: we rarely have any email correspondence outside of the USA, so we would like to block ...
- 1,914
3
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2
answers
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How do I find out what a Spam Custom Rule is?
We use a Barracuda Spam Filter at work, and we also provide a mass emailing program to some of clients that send out newsletters. Lately one of them's been composing his latest company newsletter and ...
- 719
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3
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2k
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How do you configure sendmail to reject Email with a Date header too far from real time?
A friend of mine using (I believe) qmail has it configured to reject, as SPAM, any incoming Email with a Date: header that is too far from real time. I can't figure out how to do this with sendmail. ...
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3
votes
2
answers
30k
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Allow email from a particular sender through spam filter
We are running exchange 2010 and are using the built in anti-spam feature.
We have set up Content Filtering, IP Block List Providers, Sender ID, Sender Reputation and it filters out most of the junk ...
- 473
3
votes
2
answers
1k
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Postfix - forward rejected by unknown recepients emails to SPAM-learning mailbox
I have Postfix + BitDefender FRAMS running as hygiene gateway before few Exchanges.
BD FRAMS can learn it's Baesian filter by download SPAM and HAM emails from dedicated mailboxes.
Because we have ...
- 53
3
votes
2
answers
4k
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Bayesian filtering for Exchange 2010
So here's the deal.
Basically, I am looking for a convenient way to get spam from my Exchange 2010 mail server to my spam filter/proxy (whatever you want to call it) in a mail format for ...
- 790
3
votes
3
answers
377
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Exchange 2007 ineffective spam filter
On a pretty clean 2007 setup, I'm seeing A LOT of mail with senders such as :
0.0011a7f8@roman
htyme@14009d3cb93848c
0-lz@14009d3cb93848c
0-5-1@home-4fd909062d
[email protected]
...
Benson
3
votes
1
answer
5k
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Postfix Limit mail for domain from IP range
I have multiple domains and email accounts on my postfix server. All of them get slammed with spam despite all my attempts to get it under control, I broke down and started paying for a pass external ...
- 139
3
votes
1
answer
569
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How can I explain to dspam that the user "brandon" is the same as "brandon@mydomain"
I am using dspam for spam filtering by running the "dspamd" daemon under Ubuntu 9.10 and then setting up a Postfix rule that says:
smtpd_recipient_restrictions =
...
check_client_access pcre:/...
- 547
3
votes
0
answers
112
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Combating a persistent spam list
We use Office 365 as our primary mail provider. We have an internal mail server that we use for relaying things like reports from our SSRS, scan to inbox for old scanners, etc. It is an IIS SMTP on ...
- 445
3
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0
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2k
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Accept or not to accept DKIM signed emails on my smtp server which source DNS don't has signature [closed]
In the outgoing emails we use in our domains SPF + DKIM without any problem.
But with the inbound emails some time ago we're receiving emails from some of our customers/suppliers signed with DKIM, ...
- 502
3
votes
1
answer
2k
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Exchange 2013 IPBlockListProvider blocking some (but not all) matched IPs
I have configured our Exchange 2013 Edge Transport server to utilize several IPBlockListProviders including Spamhaus. While they work great most of the time, there are still some emails which despite ...
- 31
2
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5
answers
6k
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What's a good alternative to the Barracuda Spam Appliance? [closed]
Searching for Barracuda alternatives didn't yield much. Can anyone recommend a good spam appliance like Barracuda?
I want something that will strip bad stuff out like if I have a .txt attachment ...
- 2,368
2
votes
6
answers
491
views
I'm hosting reseller and I got spam problems. Please help to solve
Our provider suspended our account with 5000+ clients and their sites. The reason was that the whole IP range was blacklisted by SpamHouse, but our provider did not explain what emails, form what IP ...
- 149
2
votes
2
answers
202
views
Best techniques to make sure that emails are not marked as spam
We have a service that requires a registration and the registration process sends some confirmation emails.
These emails say in a three-line message that you have to click some link with a generated ...
- 165
2
votes
1
answer
4k
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DMARC record is valid, but your domain's None/Quarantine policy does not yet protect it against email spoofing and phishing
People,
Using the website: https://easydmarc.com/tools/dmarc-lookup?domain=name.com
I got this error:
DMARC record is valid, but your domain's None/Quarantine policy does
not yet protect it against ...
- 1,305
2
votes
1
answer
201
views
Outgoing emails from China based VPS rejected or marked as spam
I just switched email service provider from Google apps to a VPS with a Hong Kong host. Now I find a huge part of all outgoing emails ending up in spam boxes and in some cases getting totally rejected ...
- 143
2
votes
1
answer
2k
views
Processing items with SpamAssassin and sa-learn
I have been working on getting SpamAssassin up and running for awhile now and am pretty close to being finished. However, there is one last thing that is grinding away at me that I can't seem to ...
- 790
2
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4
answers
426
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Does sending e-mail in the name of customers increase the risk of being marked as spammer?
We are developing a SaaS website application that lets users send invoices to their clients. Ideally, these e-mails should appear to be originating from our customers, so the sender e-mail address ...
- 1,082
2
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1
answer
4k
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Is there any way to see why Outlook's client junk mail filter is marking a message as spam?
I have some users running Outlook 2007 connected to an Exchange server, and they're complaining about mail ending up in their junk box. There's no X-SCL tag in the mail headers so this filtering must ...
- 178
2
votes
1
answer
775
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Postfix reverse MX check
Is there any way to configure reverse MX check for Postfix to check incoming emails?
I just noticed that most of our spam which are still coming true are sent (or seems to be sent) from properly ...
- 21
2
votes
1
answer
726
views
TXT entry in DNS for both gmail and amazon ses
It seems adding a TXT entry in DNS about Google is a good practice (when using gmail to send mail) to prevent being considered as Spammer. So I could add a TXT entry in my DNS records to:
example.org ...
- 125
2
votes
2
answers
760
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How Reverse DNS does what it does
Hopefully this is not a stupid question, but I cannot find a clear cut answer. Can someone please inform me exactly what 'source address' is used in Reverse DNS? Does rDNS pull the IP address from ...
- 185
2
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3
answers
2k
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how to stop outgoing email spam
running an email system using roundcube, with about 200 people using it.
99% of them do as they are told and only email clients they have already spoken to, however 1% of them decide to bulk spam bcc ...
James
2
votes
2
answers
849
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body_checks: How to filter base64 encoded content?
The idiomatic answer is probably "don't - use a filter that decodes the message first", but as can be seen in the second answer to that question, it should also be possible with body_checks ...
- 73
2
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1
answer
455
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Postfix change add-on priority
I have just started to fight with Spam mails because of my new project. I will explain structure of that system.
We have Postfix as MTA on relay server and fresh Spamassasian and Policyd(v2 ...
- 171
2
votes
1
answer
297
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Can IP reputation be affected due to automatic forwarding?
I am hitting a dead wall with the support team of my email hosting provider.
The IP they assigned me was blacklisted and so sending emails to AOL.co.uk end up getting rejected. After several emails ...
- 135
2
votes
1
answer
6k
views
Filter spam emails from being forwarded by exim4
I was studying and searching 2 days about how to configure my exim/spamassassin/clamd configuration.
I have the next situation:
I have an email [email protected] redirected to [email protected].
Unfortunately, ...
- 49
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2
answers
2k
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How do I allow end user 'blocked sender lists' to work even if the server manages spam filtering?
Client filtering in Outlook 2010 is disabled when the server is managing spam filtering. Unfortunately I have a few high profile users that prefer to spam-block mailing lists rather than unsubscribe, ...
- 646
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votes
2
answers
1k
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Outbound business email being marked as spam in other organizations
Wanting to make sure I've done everything I can to prevent our legitimate email from being incorrectly marked as spam by other companies:
Exchange 2010 with SP1, no major changes in 6 months.
I've ...
- 3,983