Preview app file permissions issue

I'm receiving this dialog box (see above) for a significant number of images on my hard drive when attempting to Open them with the OS X Preview application.

The odd thing is there doesn't seem to be a rhyme or reason (i.e. 'jpeg' vs. 'jpg', date, size, naming, folder and sub-folders) to which files are affected.

Also, I can view these same images with Quick Look (in the Finder); and Open them with third-party applications without an issue.

I've tried manually changing the image file Permissions via Get Info, but the default shows me as already having Read & Write privileges. I've tried resetting this via individual files (one-by-one) and as a batch in a folder, but it didn't make any difference. Those impacted remained impacted; those not impacted weren't changed, either.

Finally, this malady isn't impacting any other file types.

Ideas?