Opening the box
Be careful opening the new Airport Extreme box. It is designed so that the hardware comes flying out when the box is pulled open.
Dumb.
Really? I found that when I removed it from the shipping container that the Extreme came in a white inner box that was completely sealed in plastic. Rotating this box to the bottom quickly revealed how this box came in two pieces and basically where to cut the plastic seal.
Once the plastic seal was removed I had to gently shake the box keeping my hand underneath and the two pieces separated. Not sure why yours did what it did. At least it wasn't my experience. To add, I also got an 802.11ac Time Capsule and had the same results removing it from its packaging.