Web Articles

December 2006- Spotting HTTP Errors
by Philip Nicosia

You've all seen it on our Internet browsers: http://www.(insert name of website here)." HTTP is the protocol that sends information through the Internet. Usually webmasters will see a message similar to this, called an HTTP header.

HTTP/1.1 200 OK Content-Type: text/html Connection: close

The first outlines the HTTP protocol, and the response code that signifies the desired result of a request. The rest are field names, called response headers. All three introduce the text of the page, or the picture file.

However, a simple programming mistake can lead to errors in your HTTP headers. It's important to look at them to see if it's correct. The following are the meanings of each HTTP header to serve as a guide for your examinations.

"HTTP Status Code - 200 OK" means that the request for content was successful, and information will be sent based on the particular meto

The request has succeeded. The information returned with the response is dependent on the method used in the request.

"HTTP Status Code - 301 Moved Permanently" informs the searcher that there have been permanent URL changes. Double check that this uses one of the returned URLs. In effect, the user is informed never to return to the old address again. Use with caution.

"HTTP Status Code - 302 Found" means that the content is temporarily not found on the address (perhaps if the site is offline and is being changed). However, you are informing the client that he should still use the old website address in the future. This is similar to "HTTP Status Code 307" which temporarily redirects the user to another website.

"HTTP Status Code - 304 Not Modified" This is a conditional "Get" request. It is crucial that you check the 304 response to ensure that it doesn't contain the message body. The content ends after the first empty line after the header.

But when the message is "HTTP Status Code - 401 Unauthorized" and "HTTP Status Code - 403 Forbidden" the user is informed that the website needs authorization to allow further access to the content.

"HTTP Status Code - 400 Bad Request" means there is a syntax error and must be corrected immediately. This is also related to "HTTP Status Code - 404 Not Found" which basically says that there is nothing on the Internet matching that request. If these two messages appear, you need to go to your website programming and review it for any errors.

Another error message is "HTTP Status Code - 410 Gone" which means the resource has disappeared. The user is not directed to any new site, and this is essentially a digital version of snail mail returning with the stamp "resident not found, no forwarding address". If you have link editing functions, you should delete any references to this URL. For all intents and purposes, it's "dead".

You may also receive messages that there are glitches with the system, not the link. "HTTP Status Code - 500 Internal Server Error" and "HTTP Status Code - 501 Not Implemented" means there's a problem with the server.

XML-Sitemaps.com provides various SEO tools including a HTTP header viewer.

Note: These articles do not represent the advice or opinions of Apollo Hosting. They represent the thoughts, advice and opinions of the individual authors.