Trying to resize jpeg in Preview but says I don't have permission...

I have always resized images in Preview but this time around I keep getting an error message (screen shot attached) that I don't have permission to make any changes even after checking/changing when I right-click>Get info... I clicked on the little padlock on the corner, i changed the settings for (me) and everyone to Read & Write (screen shot at bottom of post), i deleted/copied the images again and again, renamed it, tried to Save-As, and it still doesnt work.. It's driving me crazy... Any body else having this problem?

(btw, i couldn't even resize the screenshot so that it would fit within the required dimensions, gave me the same error msg)...