I recently installed Windows 7 Enterprise Edition on one of my PC. Eager to get my PC up and running with all software I daily use, I skipped activation. When I tried to activate a few days later, I was greeted by this error message: Searching for this message, you might end up on this Microsoft support page telling you to check you DNS settings. In my case this didn't apply at all.
In the end it turns out that I ot this message because I hadn't entered my product key yet because I skipped activation during setup. To solve the issue, I:
- went to "Control Panel\System and Security\System"
- clicked "change product key"
- entered a valid product key
Windows automatically activated.