Fatal error

Hello everybody,

i just installed the plugin wordfence and got the error message:

quote
Warning: Invalid argument supplied for foreach() in /homepages/24/d107369597/htdocs/wordpress/wp-content/plugins/wordfence/wordfence.php on line 23

Fatal error: Call to undefined function wp_get_current_user() in /homepages/24/d107369597/htdocs/wordpress/wp-includes/user.php on line 209
unqoute

i cannot visit my website and cannot login in the wp backend. What shall i do. need urgent help !!!

greetings

alex

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