1. Login to your WordPress admin dashboard.
2. Under the dashboard menu, hover your mouse over Posts and click on "All Posts".
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3. Tickmark the top checkbox and all checkboxes will be automatically selected.
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4. Now click on "Bulk Actions" and select "Move to Trash" from the drop-down menu. Then click on "Apply".
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It's done. Your post is removed and no longer available for public view.