A Windows 10 bug is downgrading legitimate Pro installs to Home

Written over 2 years ago by IanDorfman

Several Windows 10 Pro users woke up to a scare yesterday when they were falsely notified that they were running Windows 10 Pro with a Windows 10 Home license.

Microsoft has put out a statement via a post on its official Microsoft Community site that reads as follows:

Microsoft has just released an Emerging issue announcement about current activation issue related to Pro edition recently. This happens in Japan, Korea, American and many other countries. I am very sorry to inform you that there is a temporary issue with Microsoft's activation server at the moment and some customers might experience this issue where Windows is displayed as not activated.
Our engineers are working tirelessly to resolve this issue and it is expected to be corrected within one to two business days

As of this writing, running the troubleshooter should resolve the issue.

Further coverage:
Ars Technica
gHacks Tech News
Windows Central