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How to Bypass Spam Filters


As a marketer, you want to make sure your email campaigns reach as many legitimate consumers as possible. However, spam filters can make it difficult even when sending legitimate mail to potential clients. If you are one of those email marketers who send out permission-based emails, you will inevitably run into the problem of overly aggressive ISP’s preventing your emails from reaching the inbox. Spam filtering affects innocent email marketers everyday, inhibiting communications efforts and threatening email campaigns.

The best way to avoid spam filters is to understand what causes filtering and to determine the standards mailbox providers use to trigger it. Even if you are sending legitimate email newsletters, you will experience the ramifications of spam filtering. Understanding how the spam world functions and the reasons that so many emails are lost in cyber space, is essential to guarantee the success of your email campaigns.

What is Spam?

Spam is the online equivalent to unwanted door-to-door solicitation. Spammers send out unsolicited emails, which contain the same message to a large number of recipients. Most spam is created for commercial advertising purposes to sell suspicious products or services. The sender can flood the Internet with several versions of the same message—with little cost to them. Most of the costs are incurred by recipients and email providers.

There are two main types of spam, Usenet Spam and Email Spam. Usenet spam is sent to newsgroups, overwhelming them with a barrage of advertising and irrelevant posts. Email spam targets individuals by sending direct email messages to stolen Internet mailing lists or web address found online. One variant of email spam is sending spam to mailing lists (public or private email discussion forums.) Spammers use automated tools to subscribe to several mailing lists at one time and to steal the lists of email address or mail the lists directly.

Spam is commonly referred to as electronic junk mail. But these bulk messages are more than just a nuisance. Spam mail often contains fraudulent offers and suspicious incentives. Their methods are designed to transmit the maximum number of messages, without regard to content or relevance, and sometimes at the risk of being unlawful. Spam can consist of advertisements for electronic devices, pharmaceutical drugs, or cash payday loans. It can contain offensive images to promote pornographic websites. It can also be hostile and contain viruses and other malware.

In addition to wasting time with unwanted e-mail, spam also consumes a lot of network bandwidth.

Most of the email marketers send out mass emails without quality content which at first seems like a viable way to increase business prospects. However, it is not worth risking the reputation of your company; it can result in major fines, not to mention that it is illegal. If you send a commercial email, it is important to understand the laws associated with Internet spam, to avoid getting yourself reported for spamming. ISP’s sue spammers under the United States federal CAN-SPAM Act, which became a law in 2004. If you violate this law, they will fine you for each offense. At a potential fine of $11,000 per offense, you are at risk for a possible multi-million dollar lawsuit.

How to Bypass Spam Filters

If email marketers are sending commercial emails to sell or promote products or services, there are a few things that they can do to avoid spam filters.

1. Use clear headers and unique subject titles:
Be sure to use clear headers that are not deceptive, and create unique subject titles. If you work in sales and you are launching an email campaign, you are probably not familiar with each person on your mailing list. But, by creating unique subject titles that are relevant to your recipients, your messages are unlikely to end up in a spam folder. Make sure all of the information you include in each email clearly indicates your product or service and the purpose of your message.

2. Include a physical mailing address and an unsubscribe link:
To avoid being labeled as spam, it is important that you include your physical mailing address, and an unsubscribe link. The unsubscribe link must work for thirty days, and you should remove recipients from your mailing list within ten business days.

3. Avoid generic sales terms:
Spam filters are more likely to divert your emails if they contain generic sales terms such as advertisement, cash, cheap, congratulations, credit, deal, debt, degree, disclaimer, free, guarantee, income, investment, marketing, opportunity, offer, profit, promotion, rich, risk-free, sales, save, spam, subscribe, trade, and winner. Avoid these terms to ward off potential reports.

4. Use a simple format and include fewer graphics:
Avoid creating email messages that read like brochures. Aside from leaving out sales lingo and generic terminology, you should also avoid using multiple fonts, large fonts, and lots of background color. Spam filters assume that any message that includes several small images is pornographic or adult content. Graphics do not add merit to your email content; in fact, they hurt your merit. Your email is much more likely to end up in the inbox if it is modeled like a business memo or an interoffice email. Use one font, one size, and one color, and put your time and energy into developing effective content rather than classic advertisements.

5. Limit the use of URL links:
Most spammers use several URL links sprinkled throughout their emails so that readers are more likely to click on at least one of them. For this reason, spam filters are suspicious of messages that contain a lot of URL links. Rather than including multiple links in your emails, establish the “next step” as a return email, and if you want the recipient to follow a link, include a single, prominent URL that does not seem dubious or deceptive.

6. Provide good content:
Include content that is reflective of your reader’s interests and attention span. There is no point in getting your email into reader’s inboxes if your content is suspicious or irrelevant. Your email should effectively communicate your content to the recipient in a way that is refreshing and engaging.

Common Mistakes

There are several mistakes new email marketers making when embarking on an email campaign for the first time. Following the five steps to avoid spam filters and avoiding these mistakes will help you to launch email campaigns that are successful and rewarding.

Avoid these common mistakes:

1. Avoid using big, bold, colorful, or flashy fonts, effects, punctuation, and capital letters. People often make the mistakes of using ALL CAPS IN THEIR SUBJECT LINE and including too many exclamation points to get their point across, which can read like spam!!!

2. Avoid sales pitch phrases or generic sales terms like "Click here!" or "Free Trial!"

3. Avoid sloppy HTML coding when converting a Microsoft Word file to HTML. Designing HTML email in Word and exporting it to HTML is messy and tends to alert spam filters.

4. Avoid HTML emails that include one large image or several small images in your emails; this is a big trigger for spam filters because they cannot translate images, so they assume that your message is spam.

How Spam Filters Work

There are many methods spam filters use to determine if your email belongs in the junk folder. One factor to consider is your sender reputation. According to a Return Path study, your sender reputation, and not your content, is the major factor that determines whether your email reaches the inbox. Their study showed that sender reputation is the cause of 83% of spam filtering. Your sender reputation or “spam score” is determined based on certain criteria.

Spam filters assign points each time they notice certain phrases included in an email message. Phrases like “Free!” or “Money Back Guarantee!” or “Buy Now!” tend to drive up your “spam score” significantly. Once your total spam score exceeds a pre-determined number, your emails are automatically intercepted and sent to the junk folder. This number varies from server to server. The list of criteria that separates spam from newsletters is always evolving to compete with clever and dubious illegitimate marketing techniques. Spam filters look for image weight and HTML coding errors; steer clear of those.

Testing your Email Campaigns

There are several tests that you can run before launching your email campaign. You can choose to go with a service like Inbox Inspector that will determine if your email will end up in the junk folder. If you do not want to use one of these services, you can run your own systematic tests to determine if your email will be filtered. Running your own tests is smart because it helps you to figure out why your email was blocked. To do this, you will need to separate each part of your email and identify at-risk content. If you find that your emails are stopped by spam filters and you want to determine why, start by changing each element in your email to see if it solves the problem. Change your subject and header; if your emails are still not making it to the inbox, remove links or URLS, change your content, remove graphics or evaluate your sales technique to make sure it does not include too many generic sales terms.

Preventing False Abuse Reports

Major ISP’s deal with millions of spam abuse reports each week; if you are not careful when you develop your email campaigns, you could easily wind up on a blacklist. Blacklisting results in an ISP blocking all email from your server. False abuse reports occur of all the time, and in fact, clean lists are falsely reported as spam everyday. It only takes a handful of recipients on your marketing list to click on the Report Spam button before there are serious consequences for your business and your reputation.

It is important that you always take steps to produce clean content and to use a legitimate mailing list to avoid spam reports. Even then, you will still receive spam complaints. There are ways to prevent false abuse reports, such as monitoring reports from ISP’s, anti-spammers, and blackhole lists. But there is no way to guarantee that you will never be the victim of a false abuse report.

Part of an ISP’s job is to prevent unwanted or junk mail from reaching their customers. They will do whatever they need to do to keep spam out, even if it means blacklisting you.

Reasons for False Abuse Reports

There are many reasons that legitimate email marketers get falsely accused of sending spam. Oftentimes, it is a simple mistake. Other times, it is the fault of the marketer. Most of the time, the reason marketers are falsely accused of sending spam is that they never bothered to ask their recipients for permission to use their email address. It might seem like common sense that if a past or potential client provides his or her email address you can send him or her mail. But, most of the time, these people are not thinking about what you might do with their email address once you have it. You have to give them the chance to opt-in to your email-marketing list. Here are some more specific instances where email marketers could be accused of sending spam.

1. Waiting too long to contact your list:
If you take the time to collect a legitimate list but wait to contact the recipients included, they may forget that they signed up to receive your newsletters.

2. Not sending out invitations:
If you participate in a trade-show, and the trade-show organization provides you with a list of attendee email addresses. This can be a great way to bolster new clients if you first invite them to join your list. Instead of jumping the gun and sending out newsletters and promos, send out invitations to attendees and include an explanation about how you got their email address.

3. Business Cards:
If you run a contest to win a free lunch or some other prize, and then you email the list generated from the contest. This fishbowl technique is often seen as a threat to recipients, because they did not give you authorization to send newsletters or advertisements when they signed up for the contest.

4. Purchasing email addresses:
Purchasing or renting email addresses from another company or organization is a common way to end up on a false report. You need to ask permission before sending newsletters and promos.

Ways to Prevent False Abuse Reports

The best thing to remember is to always ask for permission to email people, even if they are your customers. If you do not get permission, you will be reported for abuse—even if you are sending emails that are 100 percent legitimate. With that in mind, there are some other rules you can follow to prevent false spam complaints.

1. Set up a separate marketing list for your customers. Provide incentives to get customers to sign up for your newsletter.

2. Never use purchased or rented lists. Even if you acquire a legal list, sending emails to those addresses is sure to result in complaints.

3. Make sure you give recipients the option to unsubscribe. Do not make your unsubscribe link difficult to find. Place the unsubscribe link at the top of your email so that it is clearly identifiable. People who are not interested in receiving your emails are going to mark you as spam if they feel that they can’t easily unsubscribe.

4. Send out professional emails that are neat in appearance and adhere to the general rules listed above. If your email contains sloppy code or generic sales content, you will be mistaken for spam.

5. Let recipients know what you plan on sending them. If customers opt to receive your emails, make sure they know what to expect. Let each person who chooses to subscribe to your newsletter know what you will send them and how often so that they do not report you as spam.

6. Set up a list for promotions and a list for newsletters. Do not make the mistake of confusing newsletters and promotions. They are very different.

7. Do not wait to contact recipients. Set up a system where subscribers receive emails from you right away. Customers forget who you are when you wait for months or even years to contact them.

8. Do not overwhelm recipients with newsletters and promo offers during the holiday. The holidays are prime time for spammers to send emails to unwilling recipients. Avoid this by not becoming too overzealous

Email Firewalls

Email firewalls, gateways, and security appliances are just one more step in the spam filtering process. Spam is such a major concern today that ISP’s, corporations, and small businesses are all using email firewalls to filter spam before the spam is filtered. Security appliances like IronPort, Cloudmark, Barracuda Networks, Brightmail, and MessageLabs, are just some of the email firewalls out there. These gatekeepers are all over the place. They communicate with one another to determine more effective ways to block spam, and they if they even suspect that your email is spam, they will block it from ever seeing the inside of a recipients inbox.

These servers learn which email is spam mail based on feedback from your recipients. If you send out emails without permission or to recipients who do not remember subscribing to your list, they can report you to SenderBase. When you wrack up a list of complaints, they will send your information to IronPort severs everywhere—leaving your reputation in ruins. These servers rely on sender scores, or reputation scores, to filter mail before it ever makes it to the content-based spam filters. Keep your emails out of the hands of these gatekeepers by keeping your reputation in tact and sending out permissions-based emails.


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