That is why I don't keep anything important on the "system" drive, also invest into antivirus software, there are free ones and are quite good.
The last 3 anti virus softwares I tried (norton was one and the other 2 were highly respected/recommended) Only gave me problems. The last one for instance ate so many cpu cycles I could hardly move the mouse without cursor lag. It literally took 5 seconds to move the mouse from one side of the screen to the other, and it also used so much cache that taskmanager couldn't even load. It took 5 whole minutes to tell me this also.
However, the moment I uninstalled them (I tried one at a time, I'm not stupid) my computer went right back to full efficiency.
I have always hated Antivirus and believe in other security methods. So far so good, not a single virus in 15 years, none that any software detects anyway, and none that I can see draining system resources.
Just sayin', norton is like the king of bloat. I would never recommend norton, ever.
If antivirus is done right, you won't even notice it's there. I'm currently using Avast, and I've had no issues with it.
I throw an AV program my computers just in case. Generally if you're careful you won't need it.. but it's a precautionary measure.
And metro, i hate it when things like that happen. getting up early sucks.

Especially when it's for no reason because the delivery people suck. >.>