Internet connection troubleshooting

Last updated 8 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!

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!

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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.)? No. Yes.
Review your Internet connectivity (ethernet cable, wifi, 4G, proxy settings, etc.).
Review your proxy settings. Are you allowed to access that website? No. Yes.
Contact your IT support.
Load the web page in the browser. What happens? I receive "Error 404 Not Found". I receive "Error 500". I receive a "Server not found". The page loads but is empty. My credentials aren't accepted.
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. No, I'll just report it to the application owner. Ok, let's go for it!.
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). Could not find or resolve the host . Received replies. 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. It's empty or just shows some HTML code. Contains a lot of code, but doesn't render.
The web application isn't working, report it to the application owner.
Maybe your browser is not compatible, use a different browser. Ok, it works with a different browser. Already tried (Internet Explorer, Chrome, Firefox) but doesn't render.
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. Yes, I did but nothing happened (I wasn't redirected to another page nor received an email with further details). There is no forgot password option.
Great!.
Contact the application owner.
Contact the application owner.