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Questions tagged [spam]

Unsolicited e-mail, comments or posts, often sent out in large volumes; possibly but not necessarily commercial in nature

Spam can refer to:

  • Junk e-mail
  • Unwanted posts on a website
  • Unwanted comments on a post on a website
  • A large number of posts designed to crash a system rather than provide useful content

For our canonical Q&A about how to prevent email you send from being flagged as spam, see How to send emails and avoid them being classified as spam?.

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How to stop people from using my domain to send spam?

I receive Mailer Daemon messages saying certain emails fail. My domain is itaccess.org which is administered by Google apps. Is there any way I can identify who is sending emails from my domain, and how they are doing it without me creating an…
Billy Moon
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Fighting Spam - What can I do as an: Email Administrator, Domain Owner, or User?

This is a Canonical Question about Fighting Spam. Also related: How to stop people from using my domain to send spam? What are SPF records, and how do I configure them? There are so many techniques and so much to know about fighting SPAM.…
Chris S
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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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Dealing with HTTP w00tw00t attacks

I have a server with apache and I recently installed mod_security2 because I get attacked a lot by this: My apache version is apache v2.2.3 and I use mod_security2.c This were the entries from the error log: [Wed Mar 24 02:35:41 2010] [error]…
Saif Bechan
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Is greylisting still an efficient method for preventing spam?

I've used greylisting on my servers for many years, but I don't know how effective it is nowadays. Is it still good for fighting spam in 2012? Or is the typical spammer MTA capable of resending greylisted emails now?
neu242
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Is it becoming impossible to be a small mail provider?

I operate a small mail server for my private emails, some friends who have websites and two NGOs. In total my server sends between 60 and 400 messages a day. Now a lot of these emails are personal mails, between two or more people who know each…
Stefan Seidel
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How do I check a PTR record?

I need to check a PTR record to make sure that a script I have is sending emails which will actually be received by my users and not be incorrectly marked as spam. I understand that the ISP which owns the IP range has to set up the PTR record, but…
Daisetsu
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7 answers

How can I attract more Spammers hitting my Spam traps?

Currently I have a number or domains that are set up as Email Spam traps. So if I get mails on that domains I can be certain that it is ~100% Spam. I'm using this information to temporarily defer message delivery from spamming IPs on my real Email…
mailq
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Why is it a bad idea to use a customer email as the from address

I've got an application that emails users once they have filled in a form. It uses a no-reply@customerdomain.com as a from address. The customer wants it to use the email from the form as the from address which could be anything. I have been told…
Crab Bucket
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Why do 'hackers' setup bots repeatedly fill out web forms?

There is something I don't get, one of my web apps has a small form that allows you to enter you name and email address to "subscribe" to a user list for a site I maintain. The site is very low traffic, and only useful to a very small number of…
EJB
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4 answers

Prevent mail being marked as spam

This is a canonical question about avoiding outgoing mail being classified as spam. Also related: Fighting Spam - What can I do as an: Email Administrator, Domain Owner, or User? What are SPF records, and how do I configure them? I'm…
jonepatr
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Is the 10-DNS-lookup limit in the SPF spec typically enforced?

My understanding is that the SPF spec specifies an email receiver shouldn't have to do more than 10 DNS lookups in order to gather all the allowed IPs for a sender. So if an SPF record has include:foo.com include:bar.com include:baz.com and those…
John Bachir
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What happened to all the spam?

Don't get me wrong, I'm mostly glad that this happened. However, I want to make sure that the reasons for it happening are sound - rather than there being a problem with our methods. I'd like to illustrate what's going on here with a…
Ernie
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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 stop spammers from sending spam as me

We've starting to receive bounced spam messages and the sender is one of our email address. We know that we don't send spam from that address. We've tried changing the password but we're still receiving these bounced emails. Note: This email account…
hsym
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