Oracle's Flash-based "Enterprise Manager Database Express 12c" only displays a blank page

"The year is 2021 A.D. The internet is entirely occupied by HTML5. Well, not entirely... One small management console of indomitable legacy still holds out against the invader. And life is not easy for the tired sysadmins who garrison the unfortified camps of Flash, Shockwave, Silverlight and Java ..."

With the well deserved "death" of Adobe Flash at the end of 2020 everyone had hoped to finally get rid of all the clunky management consoles but life is not that nice to us sysadmins.

A few months after Flash was disabled in all modern browsers and refused to even let itself be invoked through legacy options a co-worker from our server team contacted me and asked if I had any way to still run Flash because otherwise they would not be able to access their "Oracle Enterprise Manager Database Express 12c" console anymore. And from here it all went downhill ...

Windows 10 upgrade fails with error 0x8007001F - 0x20006 ... and a number of other errors

What better pastime on a weekend than trying to upgrade a laptop with Windows 10 1809 installed on it that refuses to let itself get upgraded or install any Windows updates for that matter? I really cannot think of anything ...

But lets start from the top: This laptop has Windows 10 1809 Education installed on it. With an UBR value of 253, which puts its update status on January 8th 2019 ... more than 2 years since the last Windows update was installed.

Every attempt to install a newer Windows 10 version would always fail with the error 0x8007001F - 0x20006, accompanied with the error message "The installation failed in the SAFE_OS phase with an error during REPLICATE_OC operation." (in German: "Die Installation war nicht erfolgreich. In der Phase SAFE_OS ist während des Vorgangs REPLICATE_OC ein Fehler aufgetreten.")

And every attempt to install any regular Windows updates would throw an "This Update is not Applicable to your Computer." error (in German: "Das Update ist nicht für Ihren Computer geeignet.")

But this is just where it all starts ...