The images were 300 dpi when saved to the hard disk. I always make sure they are loaded correctly and open them in photoshop for a quick check. They are then closed and are still 300 dpi. Up until 5 days ago they were all in 300 dpi, now they are 72. There are no options to "save in a program at a particular dpi" None of the packages I work with "convert" the dpi when saving. When you store a file at 300 dpi it is 300 dpi unless you change the dpi, by either running in a batch converter or one by one. If you load an image from your camera onto your computer and the image is at 300dpi. At that moment in time, the image is saved as a 300 dpi image. If you open it in photoshop and then save, it is still a 300 dpi image. Photoshop does not change the dpi unless you ask it to. As mentioned before, this is not just my photos which I work mainly in Photoshop with. This happens with my 3d renders as well, most of them have not been opened with a graphics package since rendering and they have changed from a 300 dpi image to a 72 dpi image. I have done a quick check on the system and all the images have been modified (according to the computer) on the same date. I do know that I have not changed them because I have been too busy doing other things and my wife assures me that she has not been on the computer. I know it is not too important other than it causes me more work when it comes to printing my images. What I am trying to say here is, something is making a change to all my images and it seems to have done it as a batch (I do not have any batch file converters on that computer) If it has the ability to change the dpi then what is stopping it changing the size of images? I have not checked them all for the size. I do have a database of all my stored images, which includes original file sizes etc.. I need to spend some time looking at the data.