We just noticed that our MacBook and iMac folders indicate they are "shared" by a person whom we do not know. We have a wireless network using an unsecured "Linksys." Both Macs use Leopard operating systems. We live in 100 unit Condo building. We have read that we might secure our network with WPA2? Does this sound like an optimal choice? How do we access and install? Any other ideas. Thank you very much. T.
After securing your router, don't forget to turn the OSX firewall on too.
For Leopard, I think you go to: System Preferences --> Security --> Firewall.
The option will be under 'Sharing' if it's not under 'Security.'