Microsoft is using Known Issue Rollback (KIR) to fix problems caused by Windows 10 updates
These days, it is almost a given that an update for Windows 10 will not only fix bugs and introduce new options, it is also likely to cause additional problems. It is something that Windows users have been painfully aware of for some time, and Microsoft has been working on a solution.
And that solution is KIR, or Known Issue Rollback. The new system enables Microsoft to rollback changes introduced by problematic patches rolled out through Windows Update. KIR only applies to non-security updates.
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Writing on the Windows IT Pro blog, Microsoft’s Eric Vernon and Vatsan Madhavan explain: Known Issue Rollback is an important Windows servicing improvement to support