Error 404 Not found

It could be so many things it's pretty hard to advise. If it is random sites and you are using Internet Explorer the one thing you can try is go to Internet Options > Advanced and untick 'Use TLS 1.0'.

Failing this you can try installing another browser, run the both at the same time and see if you have issues accessing the same site from both browsers. If you do have the same problem it's more likes a firewall / router issue.
 


How do i enable tls 1.0 on google chrome ?
 


Mozilla and ie wont work either
 
Do you know that the sites actually have the file available - have you checked on another computer?

404 usually means the server doesn't have the file or it's been moved...

EDIT: The link in your example works from here (Opera 12.16, Linux, NZ. It's over unencrypted HTTP). Are you behind any sort of web filtering - could it be blocked?

Also, the 404 error page doesn't match. They've got a custom page, but yours is a real everything failed. I'd guess either server problems or someone's spoofing your traffic and sending you a 404 instead of just blocking you and getting timeout.
 


My friend checked if that site is working it works,