[VoIP] Way OT - File sharing not working under XP Pro

[Jayson Smith]

Sorry for this off-topic message, but I really need some help with this one. 
Here goes.
     We just got a new computer with XP Pro. It works great, except... File
sharing isn't working right. First off, it is saying C and D, both local
drives, are already shared, which is weird. When you try to change
permissions, it tells you this drive is being shared for administrative
purposes. The share names are C$ and D$. If I delete these shares, it tells
me they'll reappear when Windows restarts, which they do. Now all this is
fine and dandy, except that nobody else can access these shares. They can
see the computer's name in Workgroup, but there's nothing there. If you try
to run
\\computername\sharename,
as you can do on other systems, you're
asked for a username and password. The Admin's username is Client, and as
far as I know, there's no password. But that doesn't get you in. I did
disable simple file sharing earlier, in order to set file permissions. Was
this a bad move, or can you think of anything else to try?
Thanks.
Jayson