?? when i enter to mygalery.com/captcha i see blank page, if i enter to mygalery.com/captcha/captcha.php i see: Fatal error: Call to undefined function: imageftbbox() in /gallery/captcha/include/captcha.class.php on line 115
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Then you haven't applied the captcha mod properly. Undo your changes, then re-appy the mod extra carefully. Post real-life links instead of dummy, made-up ones.