It has become the great metaphysical question of the 21st century. How do you stop spam?
Trick question, really. You don't. The best you can do is restrict the flow of spam to a manageable level.
Look, I hate to be fatalistic and flip about a great metaphysical question, but the truth is spam has become so pervasive because it works. The fault for that lies with us. We are careless with our email addresses that cyber-bots eagerly harvest, giving spammers massive email lists that literally reach around the world. When spammers have that large of a target list, even a minuscule percentage rate of responses can bring significant, albeit ill-gotten profits
The good news is that restricting spam also begins with us. Using good practices while on the Internet can make you less vulnerable. If you don't practice what amounts to as common sense, even the best spam blocker you can buy won't protect your mailbox from being targeted with spam
Be smart, however, and you can fight back.
Don't spread your email around
Spammers don't go to great lengths to get your e-mail. They don't have to. You put your address up for grabs every time you post it in a forum discussion, display it on a webpage or include it in a profile. Spammers let software- generated bots do the work for them by crawling around websites and harvesting any email addresses they find left out in the open.
But of course you want people to be able to contact you, be they potentially new customers or old friends you haven't heard from in years. You handle that on your website by using a "mailto:" link for someone to send you email without displaying your actual address, or better yet, a contact form.
Social media such as Facebook and LinkedIn typically allow messages to be sent to your home pages for those services. Don't circumvent that protection by posting your regular email address on a Facebook timeline or marking it for public view in a profile page.
Opt In/Opt Out
When you sign up for an online service or make an online purchase, you may be asked to read and agree to terms that include an opt-in choice for receiving email from the company that runs the website. If it's a company you want to hear from and may do business with again in the future, go ahead, opt in to receiving an email.
But if there's a second choice asking if you want to receive email from third parties associated with the companies, your best option is to opt out of that one. You don't control what third parties will receive your email address. Even if they are legit, you may at some point want to stop getting the emails. It's easy enough to opt out of the email from the original company, but third party companies won't get that message. Attempting to identify which emails come from those third parties and opting out of receiving their messages carries its own risk.
Opt Out or Just Junk It?
The Can-Spam Act of 2003, besides its name showing a rare bi-partisan sense of humor in Congress, requires email marketers to include an unsubscribe link in the email they send you. If the marketer is operating in compliance with the federal law, you only need to click on the link, and when a new page opens, enter your email address so the marketer can take you off their email list.
You see the problem here, right - that big "If" that started the last sentence above? There are estimates that less than 1 percent of commercial emails are in compliance with the Can-Spam Act. For the rest, if you click on that unsubscribe link, you just let the spammer know that your email is a valid address and to spam away! Don't click on unsubscribe links from sources you don't know.
Beware of Emails that Look Almost Right
Just because an email comes with your bank's logo and looks pretty official doesn't mean it is official. If the email says you need to click on a link to correct an issue with your account or confirm your account information, give the bank a call instead and ask if it's legit. It's probably not. Clicking on that link would likely open you up to more spam and identity theft.
Use the Filtering Tools You Have
Email applications come with a junk folder and a filtering program to skim off much of the junk mail. You can make it work better by marking spam emails that do get through as junk rather than just thrashing them. And if emails from Dr. Yoz keep getting through with unsought medical device, you can write a rule that blacklists the doc and anyone else you identify as spammers. Do yourself a favor, however, and cruise through the junk folder every couple of days to make sure legitimate emails didn't end up there by mistake. If necessary, whitelist those senders so they can reach your inbox.
Purchase Spam Blockers
You can purchase programs or services that block spam from ever reaching your computer, holding suspect emails in a holding cell on an online server. These tend to be more aggressive in identifying spam, and the service keeps track of the IP addresses of known spammers. But just as with your junk folder, you need to visit the holding cell periodically and bail out legit messages. You're likely to get more non-spam emails held on suspicion, requiring you to more actively whitelist wanted emails, but in time, the program will improve its record of identifying the good emails and filtering out the bad. If you reduce spam to a trickle, celebrate. That's probably as good as it's going to get.