Have done a search on TD and can't find a tool to do what I want.

There are a few folders and files I want to backup on a regular basis. Specifically music files and some work files. I have a USB external drive I use for backup. When I copy from my hard drive to the external drive, I only want to replace files which are newer than the last back up to reduce the time it takes to xfer from hard to external disc.

Does anyone know of a free download tool which allows this. Or is there an, unknown to me, feature in XP that lets me do this?