We explain what to do when a web page says it is unavailable
Being greeted by a web browser showing a cryptic error message such as ‘HTTP 404 – Page not found’ or ‘HTTP 503 – Service unavailable’ is very frustrating. Although intended to help with troubleshooting, these error messages (officially known as Hypertext Transfer Protocol Response status codes, or HTTP status codes for short) were designed for technicians and offer little help to the ordinary user.
In this Quick Troubleshooter we’ll explain some of the most common error codes, and show what steps, if any, can be taken to fix the problem.
Read more: Web browsers | Web
Why errors happen
The most important thing to understand about status codes is that they come from the website, not the browser. So if one appears, it means that the internet connection is working fine, but the website is reporting a problem.
A broken internet connection, on the other hand, will result in error messages such as ‘The web page cannot be displayed’, ‘This web page is not available’ or ‘Unable to connect’. Fixing such errors is beyond the scope of this article, but malicious software can sometimes be responsible, so do check for viruses.
Restarting the router and PC is also a good idea. The same errors will also be displayed if the website’s domain (as opposed to a particular web page) does not actually exist, so try visiting some different sites.
When a web address such as www.computeractive.co.uk is typed into the address bar of a web browser, the browser translates this and sends it to the web server powering the Computeractive website.
If the website exists and understands the request, it will send back status code 200 (Success) to the browser, meaning ‘Yes, I understand the request’. The browser can then load the requested web page. If the website can’t find that particular page, it will send back status code ‘404 (Page Not Found)’ instead. Some websites redirect the browser to an informational web page if this happens.
What to do
Two common errors account for most ‘404 (Page Not Found)’ errors. The first is incorrectly typing in a website address (or correctly typing in an incorrect address) or clicking on an incorrectly made link.
Article tags
Related articles
Content Recommendation
Updating your subscription status