Advanced Sharing in XP Pro


In Runtime
Hey everyone.
I'm trying to setup a more sophisticated network between my desktop, my laptop, and my mother's desktop.

Both desktops have XP pro SP3, while my laptop has Vista Home Premium. Enabling simple file sharing with XP Pro works fine - all computers can access each others folders. However, there are two directories I only want accessible via a password. Seeing as simple file sharing doesn't offer options like that, I have turned to advanced file sharing....

I have set full control for everyone on folders like shared docs and my downloaded files, because I want any computer to be able to access it. For my private folders, I set Administrators and my User Account to full control, but nothing else.

Now, when I try to access my desktop via workgroup computers, I get that "network location is inaccessible" error. When I try to open any network place, for instance the SharedDocs, I am prompted for a username and password, nothing seems to work.

Furthermore, if I look at the permissions in the properties of the folder I'm sharing, I only see "Everyone" and any others I've added manually, and the only permissions I can tick are Full Control, Read, and Write. But, in some places I am given permissions for groups like "SYSTEM", "POWER USER", etc, and I can tick additional permissions like "Execute" and so on.

All in all, I'm finding advanced sharing very complicated and can't work out why this is happening. I haven't been able to find any tutorials on how to use advanced sharing, only step-to-step instructions on how to enable it. Can anybody help me out? Thankyou!