Stewart Williams wrote:
Sadly I have no backup as I'd just copied them from an SD card to the HDD then formated the card - maybe I was too quick doing that step.
not and answer to the disappeared folder but you could possibly try photorec. links below. the original site is not loading. might help you get back the deleted files. I had come across this software but never used it.
http://en.wikipedia.org/wiki/PhotoRec
http://www.download.com/TestDisk-PhotoRec/3000-2248_4-10511775.html
hth Raghavendra Moktali