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6. Enter admin panel of your WordPress website http://site-name/wp-admin/options-permalinkplugins.php. Scroll the page to the very bottom and click “Save Changes” button. No changes required?page=otcommerce and click Reset cache button!
7. You can check categories page on your WordPress site http://site-name/category-external/.
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CHANGELOG
The list of plugin versions: https://data.otcommerce.com/public/ot-external/CHANGELOG.txt