Header รายงานสถานะต่างๆ ของ web server ที่ตอบสนองต่อ Browser หรือ โปรแกรมที่ร้องขอไป ยัง Web Serve กำหนดไว้ดังนี้  200 คือ ปกติ ส่วนอื่นๆ คือการมีปัญหา และสาเหตุ ลองอ่านดูครับ

Header HTTP Status Codes that the Web Server can return - Definitions

1. 200 OK
2. 301 Moved Permanently
3. 302 Found
4. 304 Not Modified
5. 307 Temporary Redirect
6. 400 Bad Request
7. 401 Unauthorized
8. 403 Forbidden
9. 404 Not Found
10. 410 Gone
11. 500 Internal Server Error
12. 501 Not Implemented

HTTP Status Code - 301 Moved Permanently

The requested resource has been assigned a new permanent URI and any future references to this resource SHOULD use one of the returned URIs.

Test URI: /w3c/status-codes/301.asp

Back to Previous

HTTP Status Code - 302 Found

The requested resource resides temporarily under a different URI. Since the redirection might be altered on occasion, the client SHOULD continue to use the Request-URI for future requests.

Test URI: /w3c/status-codes/302.asp

Admin Note: 2005-03-14 - During the past several months, many discussions have been taking place in the search engine marketing communities concerning what many refer to as pagejacking. What you are about to read concerns everyone who has a website online, this is not an isolated incident. Those who are involved with the page jacking issues may not even know that they are causing harm to those they are linking to using a 302 Found redirect. Many of the 302s are generated from exit tracking scripts.

• 302 Pagejacking - The 302 Page Hijacking Exploit by Claus Schmidt

Back to Previous

HTTP Status Code - 304 Not Modified

If the client has performed a conditional GET request and access is allowed, but the document has not been modified, the server SHOULD respond with this status code. The 304 response MUST NOT contain a message-body, and thus is always terminated by the first empty line after the header fields.

Back to Previous

HTTP Status Code - 307 Temporary Redirect

The requested resource resides temporarily under a different URI. Since the redirection MAY be altered on occasion, the client SHOULD continue to use the Request-URI for future requests. This response is only cacheable if indicated by a Cache-Control or Expires header field.

Test URI: /w3c/status-codes/307.asp

Back to Previous

HTTP Status Code - 400 Bad Request

The request could not be understood by the server due to malformed syntax. The client SHOULD NOT repeat the request without modifications.

Back to Previous

HTTP Status Code - 401 Unauthorized

The request requires user authentication. The response MUST include a WWW-Authenticate header field containing a challenge applicable to the requested resource.

Back to Previous

HTTP Status Code - 403 Forbidden

The server understood the request, but is refusing to fulfill it. Authorization will not help and the request SHOULD NOT be repeated.

Back to Previous

HTTP Status Code - 404 Not Found

The server has not found anything matching the Request-URI. No indication is given of whether the condition is temporary or permanent.

Test URI: /w3c/status-codes/404.asp

Back to Previous

HTTP Status Code - 410 Gone

The requested resource is no longer available at the server and no forwarding address is known. This condition is expected to be considered permanent. Clients with link editing capabilities SHOULD delete references to the Request-URI after user approval.

If the server does not know, or has no facility to determine, whether or not the condition is permanent, the status code 404 Not Found SHOULD be used instead. This response is cacheable unless indicated otherwise.

Test URI: /w3c/status-codes/410.asp

Back to Previous

HTTP Status Code - 500 Internal Server Error

The server encountered an unexpected condition which prevented it from fulfilling the request.

Back to Previous

Header HTTP Status Code - 501 Not Implemented

The server does not support the functionality required to fulfill the request. This is the appropriate response when the server does not recognize the request method and is not capable of supporting it for any resource.

Back to Previous