Windows 7 network neighborhood PCs not showing

Recently I have been at a LAN where only one PC was consistently showing on the list of computers instead of all six. All but one PC on the network were running various incarnations of Windows 7. Some were home edition, some were Enterprise edition and some were Professional. Some editions of Windows 7 were 64 bit. One of the 64 bit PCs was always showing in the network.

Last weekend I went to my weekly LAN where I meet with friends to talk rubbish and play network games like the previous bigger LAN where I went to.

At this weekly LAN we investigated the matter and found that Windows 7 Network Sharing Center has a setting far down on the list which is not set by default and that was preventing computers from showing on the network. It was somewhere below the 128 bit encryption. The public settings did not help, this setting had to be used as well. This setting has nothing to do with the homegroup. Once I am on my home PC again, I will check what exactly it was called and will ad a mention here.