Lost Internet Connection.

[SmittySr]

I have a computer on my network that has mysteriously lost internet connection.

I can get connection if I use HTTPS but not HTTP. It seems like something is blocking port 80 but not 443.

I checked my firewall and it is not blocking IE. I also did ipconfig /all and do have a valid IP and I am able to ping my default gateway without losing packets. I have checked everything that I can think of and cannot come up with a solution.

I think that a setting has been changed in IE8. I also checked the security settings and they are set to their default settings.

Windows Vista Home Premium.

Any recommendations?

[Allan]

1) Are you using a 3rd party firewall? If so, disable it and reboot and see what happens.
2) What happens with other browsers?
3) And if you think you changed a setting in IE click on "restore advanced options"

[SmittySr]

The software firewall that I am using is built into my trend internet security suite and is set to the default settings.
The hardware firewall is the one on my linksys router and it is also set to the default settings.

I have been checking the firewall settings for port 80 an 443, and actually turned off the firewall all together, and still nothing.

Earlier today I was checking the fire wall settings and HTTP port 80 outgoing was enabled. I looked for port 80 incoming and did not see anything.

Windows Domain service on port #'s 88,135,389, 1026 was blocked, I enabled this port and I now have my internet connection again. I am assuming that the HTTP port 80 outgoing is coming back in on one of these ports.

Port 88 is the kerberos authentication system.

Port 135 Microsoft EPMAP (End Point Mapper), also known as DCE/RPC Locator service[6], used to remotely manage services including DHCP server, DNS server and WINS. Also used by DCOM

Port 389 LDAP

1026 DCOM (not familiar with this one) Distributed Component Object Model

I guess that what I am asking is if this was the right choice. It just made sense to me to unblock the DNS server incoming packets.