e-dvertising is right. You don't actually "log in" to htaccess protected content, so there is no way to actually log out. The username and password prompt that you are shown are not shown by the server, they are generated by your browser. Every time that you access a protected page, the browser is prompted for your username and password. This means that you are actually re-authenticated every time you click on a link. So that you do not need to keep re-entering your password, the browser will remember the last good password either permanently or until the browser is closed. From the server end, you do not have the ability to override this functionality.

Please note, .htaccess IS NOT SECURE as all username/password combinations are transmitted in plain text and can be easily intercepted and used by unauthorized parties to gain access to the protected content.

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