How to set Vista to allow inbound web traffic?

If your organization uses Group Policy, use the Windows Firewall Group Policy settings to configure Windows Firewall. If you have set exceptions in the windows firewall too to allow trafic and you are still not able to access your computer from a remote machine, most likely cause is the group policy is set on your computer. The Group Policy Object Editor (type Gpedit.msc on the windows search bar) provides access to the Windows Firewall settings. The settings are stored within the Group Policy Object Editor at Computer Configuration/Administrative Templates/Network/Network Connections/Windows Firewall.

Once you are in the group policy editor, navigate to Local Computer Policy -> Windows Setting -> Security Seting -> Windows Firewall with advanced security -> Inbound rules