Doc-To-Help derives topics from text formatted with heading styles in your source documents. After removing any of the headings from your source documents, Doc-To-Help deletes the existing topic when the file is compiled. Additionally, if you modify a heading in your source documents, Doc-To-Help deletes the old topic from the database and adds the modified heading. In both cases, after compiling the Help project, the modified topic is marked as deleted in the topics pane of the project editor as shown below.

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Removing Deleted Topics