Acrobat reader DC stopped working preview PDF in IE11 windows 7

Hi, I had this issue on Windows Server 2008 R2 using Internet Explorer 11.  Turns out that in the past I had disabled 'Enable Protected Mode at startup' under Edit > Preferences > Security (Enhanced).  By switching this back on, all my users no longer suffered from the crash.

The full settings for Security (Enhanced) I now use are:

Enabled Protected Mode on Startup - Ticked

Protected View - Off

Enable Enhanced Security - Ticked

Cross domain log file - Unticked

Automatically trust documents with valid certificate - Unticked

Automatically trust sites from my Win OS security zones - Ticked

File box - Empty

This is true for my environment which is Windows Server 2008 R2, Terminal Servers (Citrix XenApp), under Adobe Acrobat Reader DC version 2019.012.20034.

Hope this helps others.

Same problem here across all physical Win 7 boxes (100+ workstations).

This is only affecting PDF rendering in IE11.

(Chrome and the reader application are working fine)

Happened right after I updated everyone to 2019.008.20080.  I built a rollback script that included the cleaner tool, and reinstalled 20074.

Problem solved- Or so I thought.

Then when the update to 20081 came out the issue reared its ugly head again...

I'm holding off on doing any further Reader DC updates until I can get more information on what the cause/fix is.  We use SCCM2012/SCUP to roll out these updates.  I would rather not front-load a script with the cleaner tool to install these..