Microsoft has allegedly worked with a fix for an error in the activation server that has caused Windows 10 Pro machines to report that their license has not been activated.
The problem caused panic to some Windows 10 users who reported Reddit that the error "disabled" Windows because it switched the machine from Pro to Home, and these licenses do not match.
"Suddenly after years of having this key, which was from Windows 8 Pro, migrated to Windows 10 for free, I was notified that my key is Windows 10 Home version and that I need to install it. Wtf happens? "wrote another user on the growing reddit thread.
Another user with the same problem wrote: "Just happened to me. I had a physical Windows 8.1
Microsoft has allegedly confirmed that there is a problem affecting its activation server and working on a solution that will take place in "one or two business days."
It should mean that affected Windows 10 Pro licenses are still valid, despite what Microsoft reports.
Windows 10 user DanielRandy posted his activation issue on the Microsoft Response Forum and sent an offer that was said by a Microsoft agent.  "Microsoft has just released a news about recent activation issues related to the Pro version recently. This happens in Japan, Korea, America and many other countries," wrote the support agent.
"I'm very sorry to inform you that there is a temporary issue with Microsoft's activation server at the moment, and some customers may experience this issue that shows Windows as not enabled. Our engineers are working tirelessly to resolve this issue, and it is expected to be corrected within one to two business days, Daniel. "
Similar messages reported to be from Microsoft support agents have been posted to other threads about the issue.
@MicrosoftHelps on Twitter has simply been pointing users to the default support page for activation troubleshooting.
Since then, it has prompted affected users to provide further details in a direct message. At least, Microsoft suggests investigating.
As described by Computerworld, German readers of Günter Born's web site have described the problem in more detail:
"At least here, Windows is no longer enabled after the upgrade of the test machine. The activation troubleshooter detects a digital Windows 10 Pro license and reports that an upgrade process is required, but the following upgrade process stops immediately and activation does not occur.
License Activation (closing.exe) failed with the following error code:
hr = 0xC004C003 "
ZDNet has contact Microsoft and will update the story if it receives an answer.
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