How do I disable a pop up in Acrobat which says “ Share your PDFs using WhatsApp?”

I started getting this problem too. 

Have you tried the following (from Chris Tettamanti a year ago). It worked for me: 

1) Close out all instances of Acrobat

2) Right-click on the icon for Acrobat on your desktop

3) Click on "Properties" (it may be under "show more options")

4) Click on the "Compatibility" tab

5) Uncheck the "Run this program in compatibility mode for: Windows 8" box in "Compatibility mode"

6) Click "ok" at the bottom

7) Go back to a PDF file and click on "Edit > Preferences > General > Uncheck the Show me messages when I launch Adobe Acrobat

😎 Click "ok" at the bottom

Basically, you need to uncheck the compatibility box, and then uncheck the “messages from Adobe” button again.