Hi, i saw this was a common problem (kind of) My screen is just blank blinking in black, but id cant see any cursor. It all started with my sudo su + su that did not work in any way, i solved that problem by using my live usb and changed permissions to 0444 or something like that, (solved sudo su + su problem everything was fine at first start) then i installed some updates and now as i described above.

the only command that do works is Ctrl+Alt+Del. I still can edit everything from live usb. (I cant re install my computer since i got 1,5 TB important files.) Please help me!

Is is possible to update to 10.10 with live usb? i cant risk to drop all my files. that's the only backup and can't afford to buy a new drive since prices went up.