The Doc-To-Help Project Editor provides an additional interface for associating index keywords (KLinks) or named groups (ALinks) with specific Help topics. By creating keywords and associating topics with them, or by choosing a topic and associating a keyword with that topic, you can develop an index for your Help file in the Project Editor. Of course, you can still use Word’s {XE} fields to create index entries for print and keywords for Help targets if you prefer.
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Adding Primary and Secondary Keywords