When transferring an existing name server and the website is using a content management system (CMS) based on PHP-Nuke, you must ensure your session.save_path is vaid and can be written to. The default php.ini provided assigns /tmp as the session.save_path. If you're using the default php.ini, ensure you create a directory under /public_html called /tmp and also ensure that this directory can be written to (chmod 777).
If you've transferred your own php.ini, ensure session.save_path is enabled and accessible.
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