Connect to and Share Files with Other PCs on Your Network
Turn off Password Protected Sharing and click Apply.
There’s one last hurdle. When somebody on the network tries to see inside a Vista PC’s Public folder, they must enter a name and password from an account on that other PC; their own name and password won’t do.
Although that makes for a very secure PC, it’s overkill in a family environment. To remove that layer of security, click the word On in the Public Folder Sharing area, as shown here. When the menu drops down, choose Turn Off Password Protected Sharing.