Problem: Network Connection Folder

[Kos_Koa]

I have a problem that seems kind of weird, so I hope someone could help.

My PC's Internet connection options disappeared from the Network Connections Folder. I used that folder to enable/disable my cable connection online but now that it's empty I can't get online. I can’t even create new connections in that folder. My cable connection is split by a router to my PC, Mac, and my brothers laptop.

My Mac's connection is fine so a assumed that the problem may be with the network card on my PC. So I bought and installed a new card without replacing the old one. Now I can go online but I still can't see my connections in the Network Connections folder.

Now here is were it gets weird. My brother called from his work and told me that last night when he tried to get online his Network Connections folder was empty. So that would mean that the router could be the problem, but why would the network connections folder behave like this, and why is the Macs connection just fine?

I just can't figure out what’s wrong. Any help would be greatly appreciated!