WordPress database error: [Multiple primary key defined]
ALTER TABLE wp_s4_subscribers ADD PRIMARY KEY (`id`,`UNIQUE`,`KEY`,`KEY`,`KEY`)


Fatal error: Uncaught Error: Call to undefined function wp_salt() in /home/customer/www/spiritshack.co.uk/public_html/wp-content/plugins/spiritshack-four/spiritshack-four.php:166 Stack trace: #0 /home/customer/www/spiritshack.co.uk/public_html/wp-content/plugins/spiritshack-four/spiritshack-four.php(158): SpiritShack_Four::backfill_unsubscribe_codes('wp_s4_subscribe...') #1 /home/customer/www/spiritshack.co.uk/public_html/wp-content/plugins/spiritshack-four/spiritshack-four.php(38): SpiritShack_Four->maybe_upgrade_schema() #2 /home/customer/www/spiritshack.co.uk/public_html/wp-content/plugins/spiritshack-four/spiritshack-four.php(30): SpiritShack_Four->__construct() #3 /home/customer/www/spiritshack.co.uk/public_html/wp-content/plugins/spiritshack-four/spiritshack-four.php(591): SpiritShack_Four::instance() #4 /home/customer/www/spiritshack.co.uk/public_html/wp-settings.php(522): include_once('/home/customer/...') #5 /home/customer/www/spiritshack.co.uk/public_html/wp-config.php(90): require_once('/home/customer/...') #6 /home/customer/www/spiritshack.co.uk/public_html/wp-load.php(50): require_once('/home/customer/...') #7 /home/customer/www/spiritshack.co.uk/public_html/wp-blog-header.php(13): require_once('/home/customer/...') #8 /home/customer/www/spiritshack.co.uk/public_html/index.php(17): require('/home/customer/...') #9 {main} thrown in /home/customer/www/spiritshack.co.uk/public_html/wp-content/plugins/spiritshack-four/spiritshack-four.php on line 166