In my case maybe the router had somehow stored the apple id and the built-in Wlan allowed this alone to put me through ..
re Eichhörnchen if those PCs never had Internet contact .. were there any 3 1/2" disks involved? When using those, individual keyboard commands were sometimes stored on the game disk. This is however impossible with CD/DVD games.
Sure there is no inbuilt Wlan in this
offline PC ? Your router should not get you access automatically though, like in my case, but ..
Something something quantum entanglement.
No one understands that anyway so we can close the drawer and don't think about it anymore