Odd, when I click to the picture there I just get the picture and no warning.
I use Internet Explorer 11.
I also tried the link with Chrome, and no problem.
And I tried downloading and install Mozilla Firefox 49, to test it for you, but odd enough I only could install if I downloaded a bunch of extra software like anti malware software that I do not trust, so, I did not install Firefox. Looking at the red sign that you get, it can be, that you installed that anti malware software and that that one is giving the red sign.
Can you remember since when you get the red sign?
Could you do a System Restore to a point before you got to see the red sign? You can always undo a system restore. It is just to investigate which program causes the red sign, must have been something you downloaded recently, if you did not get that red sign in the past.