My new MacBook kept dropping its Wireless connection, every single time I opened the laptop and would wake it from sleep. Basically, I'd have to manually re-connect 2 or 3 times until the connection stuck, and I kept getting an error message saying "Error connecting to network 'jc'".
I first called support thinking it was my router. But then doing a bit of digging on the internet, I found out that this is a common issue with Macs, and there are the six simple steps to fixing it permanently:
1. Go to Preferences–>Network
2. Add a new location
3. In the Show: menu, go to Network Port Configurations
4. Make sure AirPort is checked (it should be by default)
5. Drag Airport to the top of the list (above Modem)
6. Click Apply and watch your signal meter. In about a second, it'll pop back to life.
(I also disable BlueTooth and FireWire, just because I don't need them at home)