"You need to restart your computer. Hold down the power button for several seconds or press the Restart button." I get this message everytime I turn on my MacBook Air and cannot get past it. When i turn the power off, it hang for quite a long time and this screen appears, http://www.flickr.com/photos/36836508@N04/4142594130/ Macbook Air OS x 10.5. Before this happened, i went on skype and firefox. But then it hanged, so i had to hold the power button to shut it down. I meant to restart it back but then i couldnt. This problem appears. Just before it happened, i dont have any start up application. But before, they were adium, skype and transmission. And my 'HUAWEI mobile connect broadband internet' connect automatically. and i dont use time machine. please help me.