I tried Uninstalling and Re-installing Acrobat DC from Creative Cloud, but this didn't fix the issue for me.
Deleting "linkCreation.dotm" from the following folders:
~/Library/Group Containers/UBF8T346G9.Office/User Content/Startup/Word/
~/Library/Group Containers/UBF8T346G9.Office/User Content/Startup/PowerPoint/
~/Library/Group Containers/UBF8T346G9.Office/User Content/Startup/Excel/
... helped ... for a little while. Then the file reappeared.
Doing a hard drive search, i found the linkCreation.dotm at this location too.
/Library/Application Support/Adobe/MACPDFM/DC/linkCreation.dotm
I ended up deleting the following directory:
/Library/Application Support/Adobe/MACPDFM
as well as the linkCreation.dotm file from the earlier locations too.
And so far, so good.
I noticed a day or so later (after a reboot) that a new "MACPDFM" directory appeared, but without the linkCreation.dotm file. No recurrence of the issue yet.
Hope this helps someone.
UPDATE 14 DEC 2019: Looks like the file paths may have changed in a recent update -- also check for "linkCreation.dotm" in these directories:
~/Library/Group Containers/UBF8T346G9.Office/User Content.localized/Startup.localized/Word/
~/Library/Group Containers/UBF8T346G9.Office/User Content.localized/Startup.localized/PowerPoint/
~/Library/Group Containers/UBF8T346G9.Office/User Content.localized/Startup.localized/Excel/
UPDATE 3 AUG 2021: Acrobat is back causing problems for me again, so am now using this command to purge the files causing it for me:
sudo find \
~/Library/Group\ Containers/UBF8T346G9.Office \
/Library/Application\ Support/Adobe/MACPDFM \
-name "linkCreation.dotm" \
-exec rm -i {} \;
Command will display path to the files it finds, and prompt you to confirm to delete.