Recently my laptop XP PROFFESSIONAL and my desktop XP HOME. appear ro be writing to any SD cards I download pics from. When I return the cards to the cameras the cameras state that they are blank, but only give sufficient space to actually fill space remaining on card. I can see the pics on my computers, but not now on the cameras.This has never happened before, I still use the same transfer proceedure as always e.g. open the disk & copy from the source so that I don´t get a fancy title given by other programmes. Please can anyone help me to fix this problem.