Roland Winkler, one of our Senior Writers wrote this great piece of content about common volume activation problems:

“Volume activation is designed to be a relatively quick and simple process. However, organizations still encounter a number of common errors when using volume activation. The following are solutions to some of the more common volume activation errors encountered by Microsoft customers. “

Check it out the full article at http://social.technet.microsoft.com/wiki/contents/articles/solutions-to-common-volume-activation-errors.aspx