Maintaining my privacy in a network

Ok, here's the deal. We have 3 computers in the network. It has come to my attention that someone from the other computer has been spying on my activities and files. How do I maintain my privacy in a network? Are there any programs, or can I change some settings or anything?

 

You'd have to define the type of network. I'm assuming windows of course sicne you didn't specify. But security is applied diffrently depending on the windows OS.

Typically speaking though, you just don't give the other peoples accounts access to the files you don't want them to see.

 

Depending on what OS, it can depend. If all three are WinXP Pro, I would start by strengthing the policies as to what can and cannot be done between all the machines. One is to turn off File and Printer Sharing, also by not allowing Administrator Access or even Power User Access to any user on the network.

Another is by putting the machine that is needing to be secured behind a firewall from the other machines on the network by either using a hardware device, or even as simple as a software product such as Sygate.

This makes for some great reading if you have time http://msdn.microsoft.com/library/default.asp?url=/library/en-us/secmod/html/secmod88.asp