Windows 7: How to allow file folder sharing without password When Screen Saver on

I Have a windows 7 file folder shared correctly without password between XP or other Windows 7 computers in a Workgroup. Everything is fine even when the shared computer has screen saver on and NO password protection for screen saver is set.

However, if you set the password for the screen saver, and when screen saver is on for the shared computer, suddenly other computer would have to get to the shared folder by entering user/password logon which is not acceptable for a networked application that requires file access to the shared folder.

Any suggestion would be really appreciated.