"Because volume keys are still just strings of characters in plain-text that lots of people in any large organization have access to, it's relatively easy for them to leak out," DeGroot said. "To be blunt, they were an accident waiting to happen."

With WGA, Microsoft can detect whether a volume license key for Windows is being used by a non-licensed user.

DeGroot has not heard of Microsoft fining or penalizing corporations that lose keys. But with Microsoft deactivating pirated volume license keys, companies might have to reinstall new ones on all of their computers. That can either be done remotely through an intranet, or manually by IT staffers visiting each individual PC. Depending on how involved that process becomes, it could mean up to US$25 per PC in staff costs, DeGroot said.

"It's a real pain in the butt," he said.

Microsoft is working to make the problem moot, DeGroot said. The Windows Vista client operating system and Longhorn Server OS will have volume license keys encrypted and stored on a server.