Go to your web hosting cpanel and then WordPress installation folder and open wp-config.php and scroll down just beneath the database credentials towards ' Authentication Unique Keys and Salts '.
Here you can see freshly installed WordPress doesn't provide any of the secret keys so you need to add up our own. The more random and complicated is better. The quickest and easiest way to generate strong keys values is to visit WordPress own secret keys service. Click on the following link:
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