It started yesterday when my computer randomly shut down (very quickly). I had not installed anything, and the computer didn't overheat, I was just watching videos. When I started it back up, it was unable to boot correctly, and went straight to startup repair, which did nothing (it did say ci.dll was corrupt).
After some messing around, I finally got it past the login screen with the mode "Disable Driver Signature Enforcement", but it would shut down shortly after my IMs loaded. Finally, it started working normally by starting in this mode and disabling the wireless abilities. I could still get online with a cable.
I ran a virus scan using avg and malwarebytes, but little showed up. Then, after doing some reading I thought I might've been infected with tdl4/alureon/etc. or some variant (my google pages were being redirected), and got Hitman Pro to try and fix the problem (I heard it could)
Then at some random point again, my computer shut down, and will not start in any mode! It will shutdown and reboot right at the beginning, and will not even make it to startup repair unless I make it do so. I can access the cmd now (it crashed previously) from the startup repair tools, so that's currently my only option to do repairs
What should I do? I think my mbr may be pretty messed up. I am using Windows 7 on a Gateway laptop.
It now says "A patch is preventing the system from starting"