Macbook restarts after blue screen

[Yizi]

My Macbook restarts itself after it hits the blue screen (just right before the login screen loads) sometimes it restarts, sometimes it shuts down.

Any ideas?

(Macbook 13 inch aluminum snow leopard)

 

[Yizi]

Did some testing it seem to be the power button itself!

 

[angelwatt]

Try starting up in single user mode. If you're able to then, you can try to repair permissions,

fsck -y

Let this run until completion, it may give you notices of errors along the way. Run it again until it doesn't give any errors. Once done, type in "reboot" and you'll be on your way.

That's just something to try, not necessarily a fix. Have you recently installed any new apps, or done upgrades to software or the OS? Any new hardware plugged in? From the single user mode you can also try to check some log files to see if there's any messages that may shed some light on the problem. The system log file is located at "/var/log/system.log" To see the last few entries you would use a command like,

tail -n20 /var/log/system.log

where 20 means it will display the last 20 lines of the file. I hope I have the syntax right, I'm not at a Mac currently. I'm not sure what other log files to check. Maybe someone else will have an idea.

 

[mcgovern01]

Having exactly the same problem! Any help would be greatly appreciated.
15" macbook pro 2.4ghz intel core 2 duo 4GB.

Screen goes blue, then goes to log on screen.