I'm not sure why you don't simply use the Public folder that is in your
user directory instead. That would be a better solution than trying to
share a folder at the root of C:\, a protected area. That's number one.

Number two, create an identical user account on the Vista machine that
matches the one on the XP box. I think it is better to create passwords
(you can always set the machines to log into the specific account
automatically if you want that convenience and security isn't an issue),
but you at least need the same user accounts.

Excellent, thorough, yet easy to understand article about File/Printer
Sharing in Vista. Includes details about sharing printers as well as
files and folders:
http://technet.microsoft.com/en-us/library/bb727037.aspxThis link will
take you through Vista networking very well:

Malke

Kent, you are like me; only user!

In vista, go into Netwwork and sharing, and turn OFF Password Protected.
That will stop you being asked for a password in XP when you are trying to
access vista computer