The answer to this problem begins not with your e-mail messages, but on your web page. Your subscription form itself is the first step in ensuring targeted delivery. The form should make it clear exactly what your subscribers are signing up for: what type of content and how often. If there are several different types of content you want to send out that are not likely to interest the same people, consider splitting up the information into separate mailing lists and offering your visitors the option of subscribing to one or more of them.

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