Go to your Manage Connections icon and place a check next to Wireless Network.
That will also happen if you allow the battery to get too low. It won't turn back on automatically when you charge it.
__________________ The difference between stupidity and genius is that genius has its limits. When you take things for granted, the things you are granted, get taken. Even a mosquito doesn't get a pat on the back until it starts to work. Too many people miss the silver lining because they're expecting gold.
[BES 5.0.3 / GroupWise 2012 HP2]