I would like to take up my question from 4 days ago. Pictures were taken on an SD memory card. This memory card I put in my laptop, all images appear on the monitor. Memory card back to the camera - supposedly there are no pictures on the card. This back to the laptop - and all the pictures are back from the memory card - not from the hard drive - on the monitor. Canon DSLR, Laptop with Windows 10.
Secure images to PC and then format the card in the camera.