求助：Fatal error: Call to undefined function is_blog_installed() in /data/home/……

我用WordPress建了一个自己的主页，最近发现登不上去了，进入WordPress也不行，显示的是下面的情况：


Fatal error: Call to undefined function is_blog_installed() in /data/home/qxu1589960024/htdocs/wp-includes/load.php on line 424

Warning: call_user_func_array() [function.call-user-func-array]: First argument is expected to be a valid callback, 'wp_ob_end_flush_all' was given in /data/home/qxu1589960024/htdocs/wp-includes/plugin.php on line 442


我自己完全是电脑小白，还请大神帮忙看看怎么弄啊！！！跪谢！Orz!