Apparently if you bought your copy of the Orange Box from a retailer outside your "region" Valve has started deactivating these. This should be a real public relations coup for Valve... 
http://consumerist.com/consumer/drm...-bought-orange-box-internationally-314690.php
I'm not sure in what cases this will apply (initial complaint seems to indicate it only applies to buyers of the physical box) Just trying to log into steam to see if it affects me...

http://consumerist.com/consumer/drm...-bought-orange-box-internationally-314690.php
I'm not sure in what cases this will apply (initial complaint seems to indicate it only applies to buyers of the physical box) Just trying to log into steam to see if it affects me...