Microsoft released KB4577586 as an optional update to Windows systems back in October last year. The cryptic codename hides a simple tool that is described simply by Microsoft as an update that will "remove Adobe Flash Player from your Windows machine". Importantly it will only remove Flash installations that were bundled with Windows tools – it won't remove third party or user installs.
Adobe Flash reached its end of life on 1st January 2021 and the Flash Player itself even has a built-in kill-switch that means it refuses to play content on systems where the date is later than 12th January 2021. Microsoft, Apple, Google, Mozilla, and Adobe have all acted to remove Flash from products that once used/bundled it, so you won't be able to use it in the modern versions of Edge, Safari, Chrome, or Firefox, for example.
As mentioned in the intro, you could download and run KB4577586 from the end of October last year, but Microsoft is pushing ahead with adding it to Windows Updates, as per the following schedule:
- Starting in June 2021, the KB4577586 “Update for Removal of Adobe Flash Player” will be included in the Preview Update for Windows 10, version 1809 and above platforms. It will also be included in every subsequent Latest Cumulative Update.
- As of July 2021, the KB4577586 “Update for Removal of Adobe Flash Player” will be included in the Latest Cumulative Update for Windows 10, versions 1607 and Windows 10, version 1507. The KB will also be included in the Monthly Rollup and the Security Only Update for Windows 8.1, Windows Server 2012, and Windows Embedded 8 Standard.
- Additionally, please note that when you update to Windows 10, version 21H1 or later, Flash will be removed.
So, in brief, from July KB4577586 will be included in the mandatory Windows Cumulative Update for OS version 10, 8.1 and so on. If you want to grab KB4577586 and run it for yourself now, you can download it from here.