I don't know why you're getting this. I've researched it and so far, come up with no good answers.
There is nothing on the NGA pages here that would trigger that warning, so I don't know why you're getting it. My only guess is you have some malware installed on your device there that's causing it, but that's just a wild guess. I'm going to continue to look into it.
If anyone else experiences this, I'd be grateful to hear from them.