I've had this Link Removed copying files between 3 network devices - from a linux box to a vista box, via windows 7. (e.g. win7 is man in the middle as both vista, linux are faceless devices).
I've spent the whole day trying out different combinations of a set of test files trying to pin down...
data transfer
error message
file copy
file sharing
gigabit
homegroup
linuxconnectivity
network
network issues
network performance
network printer
network settings
remote differential compression
simultaneous file copies
troubleshooting
uac settings
windows 7
windows vista
windows xp