because it is windoze update ...
... and widoze update can be surprisingly creative ... (in other words, I dunno, sorry <sigh> )
Exactly what Office 2013 bundle did you have?
Exactly what Office 2016 bundle do you have?
Update scans your system to identify what you have. Apparently it is finding breadcrumbs of 2013.
Try using the manual uninstall method described in this link to see if you can find any traces of 2013:
UNINSTALL OFFICE 2016 / Uninstall 2013 / 365 - METHOD 1 FIX IT
https://support.office.com/en-us/article/Uninstall-Office-2013-Office-2016-or-Office-365-from-a-Windows-computer-9dd49b83-264a-477a-8fcc-2fdf5dbf61d8
Office 2016 / 2013, Office 365 and Office 2013 Preview uninstalls
Method 1: Uninstall from Control Panel
Method 2: Uninstall using Fix it
Note: If you are using a 64-bit operating system, save the fixit tool on the system and then run it from the saved location.
Method 3: Remove manually
Word has a long history of requiring frequent re-installs to “fix issues”. Therefore long ago it was designed to make uninstall/re-install “painless”.
They do that by NOT removing EVERYTHING. The control panel uninstall leaves various “configuration” files (like normal.dotm) and registry entries behind to be picked up by the next Word/Office install.
If the problem is in these configuration settings it would just be carried over. The “Fix It” tool in Method 1 wipes out everything
Boot the computer before doing the re-install
http://www.thewindowsclub.com/uninstall-microsoft-office-2013-365
- This page is a “how-to” on using 27390501 and has screen captures of the whole uninstall process
NOTE: BEFORE you uninstall, if you have an “Office 2013” bundle make sure you have your 25 character product key. If you have “Office
365”, make sure you can access the MyAccount page: