Open "Network Properties" (right click on network neighbourhood).

Now it's complex (*translates the technical terms on the fly*)

Tab "Configuration":
Click "Add"
In client, install "Micorsoft Win network client" and "Individual sessions..."
In protocol, get TCP/IP, NetBEUI and IPX/SPX (in Microsoft)
In services, get "File and printer sharing for Microsoft networks".

Then in "main session..." stuff, choose "Windows opening session".

The second tab, "Identification", allows to name your comps and workgroup.

Do the same on both comps. Reboot.