Setting up a VPN connection knocks out the entire network.
Shortly after creating a VPN connection on one of the computers, the network is turned off. The router remains powered on but no internet access or access between computers is possible. At first we put it to coincidence but after 3 times, we can't figure out what is happening.
More aboutsetting connection knocks entire network
Does that computer run anything special like PPoE software for your DSL connection?