Where does the hidden firewall come from?

Question

Computer networks

A task for networkers and system administrators. One laptop is connected to Eth with internet. There is a direct WiFi connection between this laptop and another. On the first Vista, on the second W7. Everything is done by standard means. The first laptop distributes the Internet from the cord via WiFi to the second laptop. Everything works, but! Some sites don't load. All firewalls and antiviruses are disabled, DNS is not to blame, because. By IP address, they are also not allowed to visit these sites. With a direct connection, these sites work on both laptops.
Route Print of both computers does not display anything criminal, there are no exceptions or special routes. I don't know how to view protmapping of whist NAT and I can't google it.

Answer 1

What about ping?

Answer 2

by IP and will not let you into the sites. Expensive pleasure for each site by Ip. THERE always goes to the ip address of the site from dns.
Correctly comrade said about ping. Vista has no NAT. There may be a conflict of Ip addresses in the wrong route - although it's unlikely. Kom

Answer 3

Check MTU on both laptops.
It is possible that the provider uses a non-standard MTU, the one that is directly connected knows about it via DHCP, and the second does not, so its packets do not fit

Answer 4

Try to go to the site from 7 (do not try from Vista!) and look at netstat -n -a

Answer 5

Yeah, as it is expressed in the established connections, an attempt to connect.

Answer 6

there is also a strange thing:
try to play around with netsh interfaces from under the administrator in the console ...
netsh interface tcp set global
netsh interface tcp set global autotuninglevel=disabled
netsh interface tcp set global rss=disabled