Odd, occasional screenshot problem

[RikOz]

I'm running into an unusual problem every now and then with CoX screenshots that I take using the in-game screenshot function (as opposed to a 3rd-party solution). I open the image in Windows 10's "Photos" app, crop it to a reasonable size for sharing, and go to save it, except this error pops up:

 

Wut? So I look at the properties of the image file in question (this is after moving it from my SSD to my HDD, which is why the path isn't showing \CoH\Screenshots):

 

 

Notice the "Security" information at the bottom. Another computer? It most certainly did not. Also, checking that "Unblock" box does absolutely nothing.

 

The oddest part is that this does not happen with every screenshot. It's just random, every now and then, and I have no idea what's causing it.

 

EDIT: I'll also note that the only thing about it that actually seems to be "blocked" is re-saving the file after editing it. I can open and view it just fine. I can also upload it to my Google Photos account and then re-download it from there, and everything is fine.

Edited September 4, 2019 by RikOz