错误提示：

Discuz! System Error

您当前的访问请求当中含有非法字符，已经被系统拒绝
PHP Debug

[Line: 0022]search.php(discuz_application->init)
[Line: 0071]source/class/discuz/discuz_application.php(discuz_application->_init_misc)
[Line: 0552]source/class/discuz/discuz_application.php(discuz_application->_xss_check)
[Line: 0355]source/class/discuz/discuz_application.php(system_error)
[Line: 0023]source/function/function_core.php(discuz_error::system_error)
[Line: 0024]source/class/discuz/discuz_error.php(discuz_error::debug_backtrace)

Discuz官方给出的解决方法：

程序目录下载修改discuz_application.php代码。位置：\source\class\discuz的discuz_application.php
查找
private function _xss_check() {

static $check = array('"', '>', '<', '\'', '(', ')', 'CONTENT-TRANSFER-ENCODING');

if(isset($_GET['formhash']) && $_GET['formhash'] !== formhash()) {
system_error('request_tainting');
}

if($_SERVER['REQUEST_METHOD'] == 'GET' ) {
$temp = $_SERVER['REQUEST_URI'];
} elseif(empty ($_GET['formhash'])) {
$temp = $_SERVER['REQUEST_URI'].file_get_contents('php://input');
} else {
$temp = '';
}

if(!empty($temp)) {
$temp = strtoupper(urldecode(urldecode($temp)));
foreach ($check as $str) {
if(strpos($temp, $str) !== false) {