Please update to the latest version of Habitat. You can download the update at http://themeforest.net. Replace the old theme files with the new ones (make a backup first though). If you’ve made customizations you can use version.rtf (the changelog) to replace the updated files only. Afterwards you need to flush the permalinks. Go to Settings > Permalinks and click the “Save” button. Then reload/refresh the permalinks settings page again.