2010 macbook air won't shut down.
2010 11" macbook air won't shut down for the second day in the row.
I used the menu to shut down three hours ago, it cleared the desktop and has been showing me the spinning rainbow ever since.
1. how do I safely force shut down - I forgot the key combination
2. how do I prevent this happening again - anyone know what is going on?
MacBook Air (11-inch Late 2010), Mac OS X (10.7.3), Why won't it shut down?