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3. Click on OK.
4. In the Start menu, type in the Search field "search". In the results, you will see "Search how Windows searches". Click on it.
5. When the Indexing Options windows opens, click on the Advanced button.
6. When the Advanced Options window opens, select the File Types tab and select the Index Properties and File Contents radio button. In the field toward the bottom of the window, type the file extension and click on OK.
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