Você pode, mas não poderá mais compartilhar uma conexão à Internet no PC com outros computadores em sua rede local. não é recomendado desabilitar o serviço, se o Firewall do Windows estiver desabilitado no Painel de Controle, isso é bom o suficiente.
This service was named Internet Connection Firewall/Internet Connection Sharing with Service Pack 1a. It is used to allow multiple computers on your network to access the internet via only one account. This service installs on the "modem" computer. It also provides a software firewall for the system. If you are using a third party firewall, hardware gateway/router or Internet Connection Sharing software package, this service is not required. However, if you are only using a modem and not a hardware firewall/router/gateway, I strongly recommend to keep this service in Automatic.
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