Issue displaying PDF in IE11 on Windows Server 2016.

[diskserious]

We have a few Windows Server 2016 vms running in our Citrix infrastructure that publish Internet Explorer (along with other apps) to a specific group of users who require it for LOB app. There are reports that get ran and the output is PDF. This had been working fine until the end of last week. I noticed that Reader had updated on both servers with an out-of-band update released on Dec 9th. Reading through the release notes, I do not see anything that should explain the issue we are now presented with. When the report is generated, IE opens a new tab and I can see the PDF load for less than a second before it appears to close and show only a blank tab. So far, I have heard of one individual that saw this directly on their workstation. When I generate one of these reports on my workstation (also running latest version of Reader and Acrobat though Reader is set as default PDF file handler), I am unable to duplicate the issue.

Has anyone here experienced this? Any ideas of where to continue troubleshooting? I did not see aything in event viewer for the Internet Explorer logs, nor did I find anything relevant in Applications nor System.
 

[diskserious]

Even though the settings are identical to what they were before the Dec 9th patch, and they also match all of the Win 10 devices I have checked (which work fine, as before), it appears as though this only affects Windows Server 2016 (I have not tried any other ver). Turning off Reader's protected mode appears to make it work at least some of the time though it is a bit hit-or-miss.