I haven't made and changes or updated anything for some time, I have just come to log in to the store and can't nav to the admin page.
The message in the log file is:
Site is: https://www.huddlemagazine.com/[14-May-2018 12:03:28 UTC] PHP Notice: Use of undefined constant HTTPS_SERVER - assumed 'HTTPS_SERVER' in /home/huddlema/public_html/admin/index.php on line 56
And the full error log is here: https://www.huddlemagazine.com/error_log.zip
Any help will be much appreciated.