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Questions tagged [spam]

DO NOT USE THIS TAG ON QUESTIONS THAT ARE SPAM, we have a special flag for that! Questions about bypassing somebody else's spam filter are also not welcome. And keep in mind that this is a programming Q&A site, not a general computer support site. Spam is the use/abuse of electronic messaging systems (e.g. e-mail) to send unsolicited bulk messages indiscriminately.

This tag would be appropriate for programming questions about spam classification, etc.

We do not control the email filters of Gmail, Hotmail, etc. If you want to learn how to bypass them, ask the people who maintain those filters instead (but be very much prepared for "are you serious?" replies, or, most likely, no reply at all).

Understand that spammers read this site and so divulging methods for bypassing somebody's spam filters is comparable to sabotage. Please do not post such solutions.

1050 questions
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Effective method to hide email from spam bots

On my homepage, I'm using this method to hide my email from spam bots: Contact me What do you think about it? Is it effective?…
abatishchev
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Should I use the Reply-To header when sending emails as a service to others?

Suppose we have an application that acts as a middleman, allowing Company A to send reports to their customers. Company A --> Company B (me)--> Company A's customers After getting the report we send email notifications to the recipients, but they…
Gavin
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How to prevent robots from automatically filling up a form?

I'm trying to come up with a good enough anti-spamming mechanism to prevent automatically generated input. I've read that techniques like captcha, 1+1=? stuff work well, but they also present an extra step impeding the free quick use of the…
Gal
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8 answers

How to spamproof a mailto link?

I want visitors to be able to click on (or copy) an email address directly on my webpage. However, if I could make it (a little bit) harder for bots and other crawlers to get said email address and register it in a spam list, it would be awesome. I…
Wookai
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how to check if a string looks randomized, or human generated and pronouncable?

For the purpose of identifying [possible] bot-generated usernames. Suppose you have a username like "bilbomoothof" .. it may be nonsense, but it still contains pronouncable sounds and so appears human-generated. I accept that it could have been…
Tim Whitlock
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50
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18 answers

Blocking comment spam without using captcha

What are some non-captcha methods for blocking spam on my comments?
ian
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39
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6 answers

I am creating an email spammer, for an outstanding cause

In Cuba, web access is extremely censored, so I created a tool that allows more than 50,000 people to browse the Internet through email. Cubans send me an email with an URL in the subject line, and I email them back with the response. Read more at…
Salvi Pascual
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6 answers

How do I prevent mails sent through PHP mail() from going to spam?

I am using PHP's mail() function to send emails (sendmail process is running). But all the mails are going to spam (in case of gmail). I have tried many tricks that I found on the net but none is working, please tell me about any sure-shot trick.
Partyboy
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8 answers

Prevent php web contact form spam

I am an amateur web designer, I have searched on stackoverflow.com and other websites and have found many fixes for this issue I'm having, but none of them have worked (probably because I implement them incorrectly). I'm hoping someone with more…
user7858610
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4 answers

How effective is the honeypot technique against spam?

By "honeypot", I mean more or less this practice: #Register form
Your email: Choose a…
Strae
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10 answers

Preventing bot form submission

I'm trying to figure out a good way to prevent bots from submitting my form, while keeping the process simple. I've read several great ideas, but I thought about adding a confirm option when the form is submitted. The user clicks submit and a…
Mike
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26
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2 answers

rails - Choosing captcha plugin

There are a lot of captchas plugins in Rails and also many types of solutions for preventing spamming and flooding. So it isn't only Rails question. Let's see what types of plugins do we have: 1. Classic image captcha (zendesk's Captcha,…
sunki
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5 answers

Sending solicited mass email

Our company does work environment surveys, and these surveys are filled in online. All participants are sent a link to their survey in an email (personal code included). Some of our clients have employee counts in the hundreds and sometimes in the…
Christian Wattengård
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How to stop Gmail from marking mails sent by my web app as spam?

I have a simple web application that provides daily financial data. Users subscribe, and we send them an email every day. However, Gmail is marking all of our emails as spam. What should we be looking out for?
elan
24
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3 answers

Reliably detecting PhantomJS-based spam bots

Is there any way to consistently detect PhantomJS/CasperJS? I've been dealing with a spat of malicious spambots built with it and have been able to mostly block them based on certain behaviours, but I'm curious if there's a rock-solid way to know if…
Terrakin
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