macbook air turns on then off
I had to turn off my macbook air (first model) by pushing the power button. Now, when I try to restart it, I have a grey screen and hear the start sound, then the screen goes dark again with the shutting down sound. Then, the computer tries to restart again (grey screen and sound), then switches off. It does this again and again.
What can I do?
Thanks
MacBook Air, Mac OS X (10.5.8)