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Request headers
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400 Bad Request - csdtc.com
HTTP Status: 400
User-Agent: Mozilla/5.0 AppleWebKit/537.36 (KHTML, like Gecko; compatible; ClaudeBot/1.0; [email protected])
Content-Type: text/html; charset=us-ascii
Server: Microsoft-HTTPAPI/2.0
Date: Wed, 30 Apr 2025 05:13:25 GMT
Connection: close
Content-Length: 334

HTTP Code 400 Bad Request

400 status code indicates that the server cannot process the request due to client error.

When is Code 400 used?

  • When the request is malformed or contains invalid parameters
  • When required data is missing in the request
  • When sending an incorrect JSON or XML payload

What does Code 400 mean for the user?

The user receives an error message indicating that their request is incorrect and needs to be fixed.

GET / HTTP/1.1
Host: csdtc.com
Accept: */*
User-Agent: Mozilla/5.0 AppleWebKit/537.36 (KHTML, like Gecko; compatible; ClaudeBot/1.0; [email protected])
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN""http://www.w3.org/TR/html4/strict.dtd">
<HTML><HEAD><TITLE>Bad Request</TITLE>
<META HTTP-EQUIV="Content-Type" Content="text/html; charset=us-ascii"></HEAD>
<BODY><h2>Bad Request - Invalid Hostname</h2>
<hr><p>HTTP Error 400. The request hostname is invalid.</p>
</BODY></HTML>
                               

Whois info of domain