So for the second time this year my macbook has stopped working. When trying to boot, it sticks at a white screen (no Apple logo shown), and will not respond to any start-up key combinations. I did just apply a load of new updates last night whilst shutting down, so I guess they would be the most obvious culprit, but seeing as I can't get it to do anything at the moment, I'm a little stuck. Any suggestions? Or just screw it and send it in to Apple?
Try to start it up using your original install disk (holding down the C key). If it starts up normally, run a disk diagnostic to see if it can spot anything wrong. If it doesn't start up even with the disk, it's likely a motherboard issue. Either way, you may very well send it to Apple to have it checked, particularly if it's still under warranty.
