"one running windows 7 pro won't let anything access the public folder."
In an Explorer window, navigate to C:\Users -> right-click the Public folder -> Properties -> "Security" tab. Make sure that the "Everyone" group has "Full Control" - modify if that's not the case. Finally click the "Sharing" tab and again ensure that Everyone has full control. Click OK when done - you may find you need to log off then on again for any changes to take effect.