I have just deleted all the files that were on my USB, wanting to upload a whole lot more (photos), but it is saying there is no space - how can this be?? Anyone out there able to help a total luddite? There are clearly 0 items on there, but it's saying that 122.7 MB are being used, with only 118 KB free. Can anyone enlighten me on how to get rid of this mystery 122.7 MB??? Many thanks!