Whether you're new to e-mail marketing or have had a successful e-mail program for a while now, deliverability should be on your radar. Because spam has flooded inboxes with irrelevant and often inappropriate messages, Internet service providers (ISPs) such as AOL and Yahoo!, have taken a "better safe than sorry" approach by blocking any incoming message that, in their opinion, might possibly be spam. The problem with this overzealous blocking is that legitimate messages -- messages that people specifically have said they would like to receive -- are being thrown out instead of delivered. In fact, a recent study by Return Path showed that 17% of permission-based e-mail messages were incorrectly blocked or filtered by the top 12 ISPs.

While there is no way to ensure that every single message will reach its recipient, savvy marketers still should be able to achieve results far better than the industry average of 17% non-delivery. Here are some of the myths that can lead marketers to increased problems with deliverability, and how you can break through them.

Myth #1: Every name on my list has opted-in and I can prove it, so my messages will always get through.

Reality: Unlike telephone companies, which are considered "common carriers" and are required by law to facilitate communications between their constituents, ISPs control their own networks. Therefore, they can stop any message they feel even remotely resembles spam. The ISPs are more concerned about complaints from their customers than your opt-in status. And the truth of the matter is, your recipients are only human. We humans tend to forget things. If a customer can't remember where he put his car keys yesterday, do you really expect him to remember that he opted-in to your newsletter three months ago? Customers who forget are more likely to use the "report spam" button than the "unsubscribe" link. Too many spam reports will nearly always cause ISPs to block your messages.

Myth #2: To avoid being blocked or filtered, I simply need to have my company "white listed" with ISPs.

Reality: A few ISPs do maintain white lists -- lists of legitimate senders they'll let through some of their spam filters. But getting on the list is no panacea. If getting your company on the list were as simple as calling a few ISPs, don't you think every spammer would already have done it? At best, white listing might get the ISPs to turn off some of their filters if they believe you're legitimate. But if they receive even a handful of complaints from their customers, those ISPs will kick you off their white lists faster than you can blink an eye.

Myth #3: If I do run into delivery trouble, the ISP will alert me so that I can correct the problem.

Reality: ISPs are busy organizations. Billions of messages pass through their servers every day. From my experience, most ISPs won't even begin to address issues with e-mailers until their volume gets into the range of 50 million messages a month, and until the ISP can ensure the sender's legitimacy. ISPs simply don't have time to alert smaller-volume senders when they filter their messages as spam. They don't call, send polite e-mail messages, or have a website where senders can continually check their e-mail delivery status. Sometimes ISPs simply delete any messages suspected of being spam, and the only sure way to know if your messages have been delivered is to seed your lists with your own e-mail addresses at that ISP and see if you get your messages.

So what can you do?

Although the solutions to deliverability problems can't possibly be summed up in one article, one answer to these deliverability problems is simple: Get to know your customers, and they will anticipate receiving messages from you. At the very least, you'll prevent customers from reporting your messages as spam and ensure their long-term loyalty.

Understanding the truth about these deliverability myths also will help focus your marketing efforts in a more productive and efficient way, ensuring you have a successful e-mail marketing program.