Why does http take a long time to load?

Question

Computer networks

Good day everyone.
The situation is this: a computer with win7 loads data over http (port 80) for a long time, the
Internet responds with a bang, FTP from the command line works,
opened it on its server 12345 and telnetized - everything is smart. I hooked up to it with a browser and handed out html with handles - everything is also fast.
however if to try to open something on the 80th port - infinite expectation.
sinned on drweb and its gate/firewall and so on - nothing has changed after deleting the
computer is plugged into dir100, this is not observed on neighboring computers.
Scanning for viruses showed nothing.
Where else can you look for a problem?

Answer 1

Disable IPv6 on the machine. In the properties of the network card (screenshot from Windows 10, but in 7-ke everything looks comparable):
Well, for reliability, do not forget to disable IPv6 on the router altogether.
Yes, and disable Teredo and other IPv6 over IPv4 options on the machine - from sin. Run the console as an administrator and issue the commands:
(you can turn it back on using the same commands, but specifying "type=default", something like this : netsh interface teredo set state type=default ).

Answer 2

1. Check DNS. Namely what servers are used. Forcibly register your own, for example, Yandex
77.88.8.8
77.88.8.1
https://dns.yandex.ru/
2. Try to open sites not by name, but by IP address, for example,
ya.ru is 213.180.193.3
3. Try another browser , for example portable version of Firefox or something similar
4. Check the contents of the hosts file
C:\Windows\System32\drivers\etc\hosts

Answer 3

if disabling IPv6 and changing dns did not help
- try changing the patch cord and port to dir100
- try to find out the optimal packet size for this connection. tcp optimizer to help