The HTTP error 403 is frustrating to see, and quite often frustrating to solve. It rarely comes with an explanation of the exact problem that the web browser has encountered, and can be quite difficult to troubleshoot without a little further information.

As you probably know, the HTTP error 403 is received when accessing certain web pages on the Internet. There’s no way of predicting that each occasion when you’re going to receive one, and without a further reason of why you’re seeing it given, the HTTP error 403 acts effectively as the web server’s way of saying “no can do, no explanation needed”.

The most common reason for receiving an HTTP error 403 stems from accessing a page or a directory without navigating to it from a previous page. If for example, you attempt to view the directory listing of all files in a certain folder, like:

www.mysite.com/pages/

The website may be configured so as to disallow all attempted requests for directory listings. If we were to access the URL above without the pages subfolder having an index or default file, we would receive a generated list of all the pages that are located in that directory. However if “no directory browsing” is turned on, you’ll be left with an ugly HTTP error 403. This is all caused by the Check Up Down robot which follows a strict process for determining whether web content should be displayed to the requesting user. We can solve the issue by entering the full URL of the page that we’re trying to access, with the page name and extension amended to the root domain and folder. Problems with directory browsing are arguably the single biggest reason behind HTTP error 403 problems.

But they’re not the only reason.

Sometimes, when a web page is moved or re-directed to a new host on the web, the old host will throw up a 403 error to express that although the page was once hosted here, it no longer is and the webmaster is no longer around to pay his bills to keep the HTTP error 403 at bay. In this situation, we have no choice but to search out the new location of the website (if it’s moved), or go back to Google and look for any notifications of that website’s presence and status.

As you can imagine, it’s not always easy to know whether this is the reason for the HTTP error 403 on first inspection. As the first step of troubleshooting, you should try to access the root domain. Some web hosts will be nice enough to leave a re-direct or notification in place. And you’ll at least be able to see whether the web page is only partially accessible, or if its HTTP error 403 ridden throughout.

You should also be aware of the possibility that a subfolder may exist without a page being added to it. In this case, an HTTP error 403 is often thrown as default by the web server. If Basic HTTP Authentication is turned on, you will, of course, be required to enter a valid username or password to bypass the standard HTTP error 403.