So I was using my mac, and got the security update via software updates. I installed it, restarted it, and now the operating system isn't there. When I hold option on start-up, it only gives me an option of Windows - even though I don't have boot camp anymore - I did a couple days ago but got rid of it. I do have vmWare though. Anyway, where did my mac go? I'm on the verge of panicking here. Any ideas what happened, and how to get it back? Thanks.