SA won't start anymore and shows NTVDM error

[Szayelaporro Granz]

This appears when I launch SA (see attachment). Yesterday it worked, the error appears just today. On top of that, not even custom.exe launches anymore, it only briefly shows a window without any error message. I'm using Win7 until I go back on Wednesday.

[Drake]

Woah, what the heck? Why is NTVDM even running? SA isn't 16-bit.

[Szayelaporro Granz]

On other Win7 laptop SA doesn't even launch at all, though config.exe still works.

Another note: Suddenly, it always launches on compatibility mode even though I never do that before. This is also the case yesterday.

[Drake]

This almost sounds more like an issue with your particular installation, if another computer is getting similar issues. Like, the fact that an NTVDM prompt came up at all is totally baffling. The fact that it runs on some compatibility settings sort of confirms something crazy is going on with how the game is being executed. I forgot to ask if you have any other Touhou games and whether those run properly.

Back up your score file and replays and see if reinstalling the game does any good.

[Szayelaporro Granz]

Nope, only SA is doing weird. Other games run properly.

I'll reinstall it tomorrow, on my Win8.1 laptop though if it also doesn't work.

[Szayelaporro Granz]

Oh, it turns out to be some virus -_- Reinstalling the game helps apparently.