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412 Precondition Failed - hdu.com

HTTP Status: 412

User-Agent: Mozilla/5.0 AppleWebKit/537.36 (KHTML, like Gecko; compatible; ClaudeBot/1.0; [email protected])

Date: Wed, 30 Apr 2025 09:35:42 GMT

Server: Apache

Upgrade: h2

Connection: Upgrade

Accept-Ranges: bytes

Content-Length: 1004

Content-Type: text/html

HTTP Code 412 Precondition Failed

412 Precondition Failed indicates that one or more conditions in the request header fields were not met by the server.

When is Code 412 used?

When a request contains an If-Match or If-Unmodified-Since header that fails validation
When an API request includes preconditions that the server cannot satisfy
When a resource update is attempted with outdated conditions

What does Code 412 mean for the user?

The request is rejected because one or more conditions are not met. The user may need to refresh data or retry with updated request parameters.

GET / HTTP/1.1
Host: hdu.com
Accept: */*
User-Agent: Mozilla/5.0 AppleWebKit/537.36 (KHTML, like Gecko; compatible; ClaudeBot/1.0; [email protected])

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
	<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
	<title>412 Request Blocked</title>
	<link href="/icons/expired/style.css" rel="stylesheet" type="text/css" />
</head>

<body>
	<div id="notice">
		<h1>412 REQUEST BLOCKED</h1>
		<h2>Precondition failed: the web server has blocked this request for security reasons.</h2>
	</div>
	<div>
		<p>You may want to contact the webmaster and inform them <br />
		of the time the error occurred, as well as anything you might have <br />
		done that may have caused the error.</p>
		<br>
		<p>If you are the owner of the website, you can get more information about <br />
		the issue and how to resolve it in the article <a href="https://tickets.suresupport.com/faq/article-1596/en">Error "412 Precondition Failed" (mod_security2)</a>.<br /></p>
	</div>
</body>
</html>

Whois info of domain

Domain Name: HDU.COM

Registry Domain ID: 480729_DOMAIN_COM-VRSN

Registrar WHOIS Server: whois.domain.com

Registrar URL: http://www.domain.com

Updated Date: 2025-03-14T03:47:20Z

Creation Date: 1997-04-11T04:00:00Z

Registry Expiry Date: 2026-04-12T04:00:00Z

Registrar: Domain.com, LLC

Registrar IANA ID: 886

Registrar Abuse Contact Email: [email protected]

Registrar Abuse Contact Phone: 602-226-2389

Domain Status: clientDeleteProhibited https://icann.org/epp#clientDeleteProhibited

Name Server: NS1.S416.SURESERVER.COM

Name Server: NS2.S416.SURESERVER.COM

DNSSEC: unsigned

URL of the ICANN Whois Inaccuracy Complaint Form: https://www.icann.org/wicf/

>>> Last update of whois database: 2025-04-30T09:35:35Z <<<

For more information on Whois status codes, please visit https://icann.org/epp

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