For the past several weeks, Microsoft has been investigating why a specific Windows 10 update was slowing some PCs down to a crawl. Apparently it has finally found the issue. It also has released a new update (KB4576754) to replace the problematic (KB4559309) one that was being forced onto some PCs.

The main purpose of KB4559309 was to

Source: Hot Hardware – Microsoft Replaces Windows 10 KB4559309 Update Following Reports Of PC Slowdowns