If you use an ethernet cable to directly connect your PC and your mac, I think you need to give the Mac the windows workgroup settings. You definitely have to do this if you use a router.
If you right click on "Network Neighborhood" on the Win desktop, and choose properties, there should be a tab in there with three blanks -- identification, workgroup and description.
I think these have to be put into the network preferences on the Mac -- at least, if you use a router, they do. Not in front of my ibook right now, so I can't confirm.
I can say I went through figuring this out only a few days ago.
Setup:
Windows PC -> Linksys router ->Yahoo/SBC DSL modem
iBook -> Airport Ex base station -> Linksys router -> DSL modem
What I found by trial and error:
1) If you have one, you need to disable the firewall or change the settings on the computer from which you are *taking* files (that is, if you want to open the PC hard disk on the mac, then you have to temporarily disable the PC firewall, or at least make it allow file sharing).
2) You have to tell the Mac the PC's windows workgroup ID stuff as mentioned above (can anyone help on specifics? otherwise I'll try to do it next time I'm by my iBook). Also in the Network Neighborhood properties, on the first tab, is a button marked "File and Printer Sharing." You have to click this and in the window that pops up, choose file sharing.
3) On the PC, you have to define which devices can be shared. If you want to share the whole C: drive, you go to My Computer, right click on the C: drive, and choose the sharing tab (which will only be there if you did the second half of step 2). The options here should be self explanatory. You can also do this to individual folders (if you make a drive or folder shared, everything inside it becomes shared).
4) Then, when you plug in, you open a Finder window (iBook) and click on the network icon on the left side. You should see your PC in the list with the name that was in the "Identification" field in Network Neighborhood / Properties / Identification. When you open it you will get prompted for the password you created in step 3.
Notes:
For me, at least without too much hacking, I found the following to be true:
- If the PC is cabled into the router / DSL, and the Apple is on the Airport, this DOES NOT WORK. (OT: is this a simple setting issue or designed in for security? AFAIC, I would prefer the latter). The PC and Apple must both be on the same router (or maybe plugged into each other directly).
- Sometimes you have to try clicking the network icon in Finder a few times before the PC comes up. Maybe if you reboot the Apple after you followed steps 1-3 this wouldn't be an issue?
Anyway, long and confusing, but that's how you go about it....