After many tests, he found that KB971033 (which should not have been installed at all in a KMS environment) was installed on these machines and causes this issue. The thread starter found suddenly a few thousand Windows 7 VDI machines that reported that Windows 7 was not genuine. Removing the update, deleting the KMS cache and activation data from the PC's and re-activating against KMS resolved the issue. Until today having this KB installed hasn't been an issue, it appears a change to how Microsoft's activation servers respond to a standard KMS key being sent to them may be to blame. After much troubleshooting we found that KB971033 (should not have been installed in a KMS environment in the first place) was installed on these machines. Woke up this morning to find a few thousand Windows 7 VDI machines reporting that Windows 7 wasn't genuine. PSA: Windows 7 Genuine Advantage – KB971033. On reddit there is this thread which describes the drama. Since then, admins have complained about Windows 7 clients that are no longer activated.
#Reddit windows loader update
Woody Leonhard wrote that night that Microsoft has re-released the KB971033 update for unknown reasons.
There is a new activation update there to ensure that Windows 7 can be activated. The description for update KB971033 was last updated on Apand deals with the topic Windows Activation Technologies for Windows 7.
I just stumbled across the topic at, where it hit enterprise clients with Windows 7.