I thought I'd cracked all my problems recently (!) but tonight, I pressed the Publish button and I get this:
Fatal error: Call to undefined function mb_encode_mimeheader() in /home/dreamers/public_html/cms/wp-content/plugins/subscribe2/classes/class-s2-core.php on line 354
I can't think what I've changed. Maybe a plugin or two, but nothing drastic..
Best action to resolve?