error access wpadmin

Fatal error : Uncaught Error: operator not supported for strings in /home/customer/www/bottegadarteantichita.com/public_html/wp-content/plugins/revslider/inc_php/framework/base_admin.class.php:73 Stack trace: #0 /home/customer/www/bottegadarteantichita.com/public_html/wp-content/plugins/revslider/revslider_admin.php(237): UniteBaseAdminClassRev::addMetaBox(‘Revolution Slid…’, Object(UniteSettingsAdvancedRev), Array, NULL) #1 /home/customer/www/bottegadarteantichita.com/public_html/wp-content/plugins/revslider/revslider_admin.php(68): RevSliderAdmin->addSliderMetaBox() #2 /home/customer/www/bottegadarteantichita.com/public_html/wp-content/plugins/revslider/revslider_admin.php(40): RevSliderAdmin->init() #3 /home/customer/www/bottegadarteantichita.com/public_html/wp-content/plugins/revslider/revslider.php(147): RevSliderAdmin->__construct(‘/home/customer/…’) #4 /home/customer/www/bottegadarteantichita.com/public_html/wp-settings.php(305): include_once(‘/home/customer/…’) #5 /home/customer/www/bottegadarteantichita.c in /home/customer/www/bottegadarteantichita.com/public_html/wp-content/plugins/revslider/inc_php/framework/base_admin.class.php on line 73

Connect the website through FTP and rename Revslider folder ( /public_html/wp-content/plugins/revslider/ ). It should work fine after.