XP ome folder protect

[Tom]

Hi,

I have 3 PCs (call them A, B & C) at my home all connected with wifi.
They all use XP Home SP2. They can all see each other. How do I set
things up so B can access a folder on A, but C is denied access to
that same folder?

Is there some freeware that can do this? Does it require XP Pro?

I tried booting up A in Safe Mode to change the permissions. But B & C
could still access the folder over the network.

I do not want to encrypt or compress the folder on A. I just want to
password protect it.

Thanks,

Tom