What's the fucking shit with you, MS, pic.twitter.com/Bw9n7MbJ7v — FaiKee (@FaiKeeF) November 8, 2018

For reasons that are currently unclear, Windows 10 Professional users are finding that their properly licensed installations are being deactivated.

On systems affected by the issue, Windows is complaining that a Windows 10 Home license key is being used with a Windows 10 Pro installation. To fix things, the system needs to be wiped and Windows 10 Home installed. Otherwise, a genuine Windows 10 Pro key needs to be used.

Microsoft has acknowledged that the problem exists and that some unspecified issue with the Windows Authentication servers is causing the problem, but as yet, there's no fix. The Windows 10 Pro licenses do seem to be valid, and some resolution is promised within a couple of business days.

Update November 9, 2018:

Microsoft has issued the following statement:

A limited number of customers experienced an activation issue that our engineers have now addressed. Affected customers will see resolution over the next 24 hours as the solution is applied automatically. In the meantime, they can continue to use Windows 10 Pro as usual.

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