Adobe announced a radical overhaul of their activation process for volume licensing customers with CS6. CS4 & CS5 activated in the background as soon as the software detected an internet connection; so no action was required. CS6, however, requires active registration online or the product will stop working.
Where this has caused problems is in the realm of Enterprise Deployment; those attempting to deploy an image over a network have come across serious activation issues.
Fortunately Adobe offers a free Enterprise Deployment Toolkit (AAMEE) to resolve this problem; it’s effective and easy to use.