It is both photos and videos that I have attempted to overwrite on 2 separate laptops. When in thumbnail mode, I have attempted to overwrite a photo it just says 0 files overwritten in 0.9 seconds. I attempted one in the llist view and it showed the file to be in an 'excellent state'. I tried to secure overwrite and it came up with the same comment '0 files overwritten'. There is also the comment - 'no overwritten clusters detected' as stated previously. Thanks