The suggestion to upgrade PHP version to minimum 5.6 OR replace the content of header.php has essentially been done. I am using PHP version 5.6.32 and have been since the issue began. I have not replaced the header.php and would prefer another workaround. I have 15 or so sites with the same basic configuration – Enfold, Wordfence, Yoast SEO, etc. and I’m concerned with updating to the latest version of Enfold if this will need to be done on all of those sites.

I’ve had two sites that I’ve updated today go down when updating to 4.2.6 from 4.2.5. They’ve had similar configurations: php 5.6, WP 4.9.5, Wordfence 7.1.2, All in One SEO 2.5. I received an http 500 error. Thanks for any help.