I've finally got round to automating my data backup process. It's not been running for long so may get refined, but it's a lightweight solution using a batch file and the ROBOCOPY command with the /mir switch.
I simply list the source and destination folders and run it.
It seems to be very clever. The first time I run, it copies everything to the backup drive - including sub-folders. Subsequent times it only copies and overwrite files which have been modified. Any new files added are also picked up and copied and what's really nice is that any files deleted are also deleted from the backup. So it really does mirror.
As only new and modified files are copied across, subsequent runs are relatively quick.
I couldn't get the mirroring of deleted files to work with XCOPY. Also, it was just skipping a top level directory for some reason. I didn't solve this - I used ROBOCOPY instead.
I think ROBOCOPY is only available on Vista and above - so possibly not on XP. I'm using Windows 7.
I just need to think now of the best way and time of running the batch file...