Hoping someone can help with this problem: My macbook air after awaking from sleep sometimes disconnects from wifi. The menu bar still shows full bars and when I highlight my mouse over the icon it says wifi is on but does not show any networks. I then restart the computer and it will show a flashing folder with question mark. I have to end up doing a hard reboot and it works fine after. I am using a 2013 11" macbook air and on OSX 10.9.2. Any ideas how to fix this or what may be wrong?