Image files decrease in size when being moved?

[OneJuan]

Hello,

I have found myself in a rather frustrating situation. I moved some jpeg photograhps from "My pictures" folder to another folder on the local hard drive by dragging the files and therefore moving them. They were moved successfully, however there is one catch.

Before I started moving these files I copied all the files on my local hard drive to an external one for backup. I noticed that most of the photographs that I moved by dragging to another folder decreased in size. For example, one of these photographs used to be 5.18MB and now it is 4.73MB. When I open these files and compare them with windows photo viewer I spot no difference whatsoever, same when I compare the colour graphs in Lightroom. Also the resolution is 6000x4000 like the original.

Since I did a backup it's not the end of the world, however I would like to know what is going on. Should I replace those files with backup ones or are files smaller than original because they now lack some useless metadata?

Thank you

Juan

[DeborahJ]

Even I have noticed that. At times some hidden files maybe left behind in the old folder, so the new folder where the files have been moved may show a smaller size.

But you have noticed this for individual image files. Is this the explanation you were looking for?
https://technet.microsoft.com/en-us/.../cc976801.aspx