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Questions tagged [spam-filter]

179 questions
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8 answers

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 Practices for preventing you from looking like a spammer…
kcode
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Best Practices for preventing you from looking like a spammer

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. reverse DNS (PTR) records are pretty much a…
gravyface
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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 filter as described on…
user48058
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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 recipient's mail address but not on how to do it for…
mailq
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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 with an after-queue filtering, the email would be…
pepoluan
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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 spam with no much luck. What would be on your…
Igor
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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…
Dennis Gorelik
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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-filter approach. Which approach is faster? / Which…
tex
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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 outputs ; <<>> DiG 9.9.5-3ubuntu0.8-Ubuntu <<>>…
nulll
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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 blacklisted. This is a header from a server…
TenJack
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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. Is this level of spam going to impact on our…
Steve
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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 flags and by modifying the message subject. When…
user71061
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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) smtp.mailfrom=mydomain.com; hotmail.com; dkim=pass…
Raptor
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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 reports of blocked and quarantined outbound emails…
HopelessN00b
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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 first of the year, our Barracuda began tagging a…
Jasoomian
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