The Apache access encountered 501 Method Not Implemented error

Today, when I opened the website, I found 501 Method Not Implemented to/index. html not supported. I used apache environment.

Some friends say

The server loads the security_module module.
If the server side solution is available
Will/etc conf. d/mod_security. conf

loadfile /usr/libxml2.so.2
loadmodule security_module modules/mod_security2.so
loadmodule unique_id_module modules/mod_unique_id.so

Comment it out, and you're done.

Or it could be
Add the following to htaccess

<IfModule mod_security.c>
SecFilterEngine Off
SecFilterScanPOST Off
</IfModule>

Turn it off.

Foreign websites find 1 solution.

$ telnet www.example.com 80
Trying 192.0.32.10...
Connected to www.example.com.
Escape character is '^]'.
OPTIONS / HTTP/1.1

HTTP/1.1 200 OK
Date: Tue, 08 Dec 2009 02:29:38 GMT
Server: Apache/2.2.3 (CentOS)
Allow: GET,HEAD,POST,OPTIONS,TRACE
Content-Type: text/html; charset=UTF-8
Content-Length: 0
Connection: close

Connection closed by foreign host.
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