I have a fresh Windows 2012R2 installation.
Updates are coming via WSUS (Only security and critical).
This server has no internet connection.
I need Flash to be enabled.I don't have any Flash Extensions available in the add-on in IE11.
Microsoft embeds Flash in IE in Server 2012R2, however, it's only visible when the end-user enables Desktop Experience.
Since Microsoft embeds Flash in IE all updates are distributed by Microsoft via Windows Updates, due to this, the Flash Player ActiveX Control installer does not run on Server 2012R2 (nor any other flavor of Windows where Microsoft embeds Flash in IE/Edge).