"Unknown Publisher" problem?

[Gallium Spoon]

Hi, I got my copy of Amnesia from Steam, and I've had a series of problems.

First, the game would crash on launch, but I resolved that by updating my drivers.

Then, I had the infamous black screen problem where the game would run but I can't see anything. I'm pretty sure now that it's because my integrated GPU is interfering with the discrete GPU, and thanks to the "AMD + Intel HD Troubleshoot" thread I think I'm on the verge of solving that.

But now I have a new problem. Since the last time I restarted my computer, my computer has been refusing to run Amnesia. When I attempt to launch the game now (whether from the launcher or directly) I get a message asking me if I "want to allow this program from an unknown publisher to make changes to your computer?" When I click "Yes" it just sends me back to the launcher, where if I attempt to launch the game, the same message shows up again. It's an endless cycle.

I don't understand why I have this problem all of a sudden and I don't understand why my computer doesn't understand what I mean by "Yes".
Admittedly I am new to Windows so there might be a problem there.

Thanks for any help.

[jens]

Try verifying cache integrity on the game (in steam right-click on game, select properties and then in one of the tabs you'll find it). Or perhaps delete and install the game completely from scratch.