Internet connection troubleshooting

Last updated 5 years ago First published 19 August, 2016

When you connect to a remote service (website, email, FTP, etc.) there are many different elements involved. If any of them fails, you won't be able to connect.

Here I've created a troubleshooting decision tree to help you find out why can't you browse a website so when you contact a helpdesk they will be able to solve your problem faster.

I hope this helps!

Computers,Technology English Rating: ALL ages Shortest path: 3 nodes Longest path: 17 nodes Possible solutions: 17
Andrés Méndez I've been always passionate about knowing how everything works, and the Internet wasn't an exception, so to learn more I became a white hat hacker, and I really love it!
Transcription
  • Where are you trying to connect? I'm trying to browse a website. I'm trying to acces my email using an email client (no web browser).
  • Sorry, come back later, I haven't completed this branch :-).
  • Can you browse any other website (Google, Yahoo, etc.)? Yes. No.
  • Review your Internet connectivity (ethernet cable, wifi, 4G, proxy settings, etc.).
  • Review your proxy settings. Are you allowed to access that website? Yes. No.
  • Contact your IT support.
  • Load the web page in the browser. What happens? I receive "Error 500". I receive "Error 404 Not Found". My credentials aren't accepted. The page loads but is empty. I receive a "Server not found".
  • The URL you're using is wrong, please request a new URL.
  • The web application fails, report it to the application owner.
  • The URL is wrong, the webserver is down or unreachable. Let's narrow the problem. Ok, let's go for it!. No, I'll just report it to the application owner.
  • Ok, but with no further details wait seated for a solution.
  • Try to load the URL with http:// and https://. One of them worked. None worked.
  • Which one worked? http://. https://.
  • Then the problem is in the webserver security configuration, report it to the application owner (not using HTTPS is insecure).
  • The problem is in the webserver security configuration, but you can use confidently the HTTPS website.
  • Open a command line console and ping just the hostname (ping www.example.com). Don't ping the URL (http://www.example.com/index.html). Received replies. Could not find or resolve the host . Received no reply (request timed out).
  • The URL is wrong, or the DNS is down, report it to the application owner.
  • The server is working, but the web service is down, report it to the application owner.
  • The webserver can be down or there is a firewall blocking ICMP. In the console execute a traceroute (tracert on Linux) to the hostname. Ok, done.
  • Report the traceroute results to your network administrator and the application owner.
  • Look at the source code of the webpage. Contains a lot of code, but doesn't render. It's empty or just shows some HTML code.
  • The web application isn't working, report it to the application owner.
  • Maybe your browser is not compatible, use a different browser. Already tried (Internet Explorer, Chrome, Firefox) but doesn't render. Ok, it works with a different browser.
  • Great!.
  • The web application isn't working, report it to the application owner.
  • Can you restore your password? Yes, I did and now I can access. There is no forgot password option. Yes, I did but nothing happened (I wasn't redirected to another page nor received an email with further details).
  • Great!.
  • Contact the application owner.
  • Contact the application owner.