Avoiding Spam Filters (for end-users)

I am frequently disturbed by how often the built-in filters in either Outlook or Thunderbird misdiagnose messages as being spam. Similar issues can plague server-side spam protection.

Some filters are smarter than others, but most of them look for similar things. Here are a handful of tips end-users can follow to drastically reduce the odds of their email messages getting vaporized.

Don't include silly little images in your email. This applies doubly for silly big images. Images are a major hallmark of spam email.

Try to avoid excess HTML formatting in your messages. This includes using multiple font sizes or faces, custom background colors or use of tables. All of these things are commonly used by spammers to obfuscate content, or otherwise make their messages appear as intended. If you really want to be safe - consider avoiding the use of HTML completely by setting your email client to plain-text.

Avoid including a long legal disclaimer at the end of your messages. I understand some companies require these, but the reality is they look a lot like spam. Copyright notices or anything making a proclamation as to why "this message was sent to you" looks like a spammer trying to cover their butt from a legal standpoint.

Try not to include a large number of lengthy URLs in your messages. They can look suspicious. Tiny URL is a good way to cut them down to size - and makes life easier for the recipient to boot.

Links that have custom anchor text, or other special formatting are extra-risky.

Avoid typing in ALL CAPS or using excessive exclamation marks!!! Calls to action like, "Call us today" or "Click here" can also cause problems.

In short - your email should look like an email message - not a webpage or advertisement.

If you use an email signature all of the above guidelines also apply to it.

Don't send email from a free webmail account like Yahoo! (Gmail is probably OK). Many free webmail services append advertising to the bottom of your email messages. This looks like spam. I've known a handful of server administrators to block such accounts wholesale. I think this is a bad idea, but it does happen.

Don't use freeware email utilities that append things like "My Inbox is Protected by Blingsoft Anti-Spam! Click this link for more information." Again, this looks like spam itself.

Do not, I repeat, do not use Incredimail or similar products for all the reasons listed above.

Avoid spammy topics. The primary ones involve matters of sex and or money. Don't mention the V-word (that pill Bob Dole takes) - even in passing. I'm not suggesting self-censorship - it's just that free expression doesn't do you any good if your email is sitting in the junk message folder.

If you want to discuss these topics - try to have the recipient "whitelist" you first. Most client-based spam filters support a whitelist or list of "known good senders." Unfortunately, many server-side filtering systems lack this functionality, or it at least isn't readily accessible by anyone other than the server administrators.

Avoid specifying a different "reply-to" address than the normal account you send from. Again, it looks suspicious.

Don't send email from a .INFO domain. .INFO domains are widely available and super-cheap to register. For these reasons, spammers love them and spam blocking applications hate them. Also - be sure not to include any URLs containing .INFO domains within your messages.

If you're located in Asia, Africa or Russia and exchange a lot of email overseas, consider setting up an email account located in Europe or America. The tough news is that a lot of spam filters keep track of "suspect" countries which send a lot more spam than legitimate email.

Make sure your outgoing email server isn't listed in major blacklists like the CBL or Spamhaus. Among others sites, MX Toolbox provides a tool that lets you do this. Most servers are listed in one or two minor blacklists. If you think there's a problem - contact your ISP. If your ISP can't resolve the issue - you may need to find another internet provider.

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