Fatal error: Uncaught Error: Call to undefined function trailingslashit() in E:\demo.solarfast.co.uk\wp-includes\class-wp-textdomain-registry.php:103
Stack trace:
#0 E:\demo.solarfast.co.uk\wp-includes\l10n.php(784): WP_Textdomain_Registry->set()
#1 E:\demo.solarfast.co.uk\wp-includes\load.php(1401): load_textdomain()
#2 E:\demo.solarfast.co.uk\wp-includes\load.php(278): wp_load_translations_early()
#3 E:\demo.solarfast.co.uk\wp-settings.php(74): wp_maintenance()
#4 E:\demo.solarfast.co.uk\wp-config.php(115): require_once('E:\\demo.solarfa...')
#5 E:\demo.solarfast.co.uk\wp-load.php(50): require_once('E:\\demo.solarfa...')
#6 E:\demo.solarfast.co.uk\wp-blog-header.php(13): require_once('E:\\demo.solarfa...')
#7 E:\demo.solarfast.co.uk\index.php(17): require('E:\\demo.solarfa...')
#8 {main}
  thrown in E:\demo.solarfast.co.uk\wp-includes\class-wp-textdomain-registry.php on line 103