I recently upgraded by purchasing a subscription to Office 365 Home and found that I could not open any Word or Excel documents using the new 2016 versions. (And yes, I could still open my old files with all of the old versions.) I've been reading and reading
the forums in hopes of solving the problem. I was incredibly frustrated and ready to request a refund. And then…
After reading CGNZ's post I decided to try using my font manager's (FontExplorer Pro) tools to clean application caches and to deactivate all of the fonts on my system. I also used it to "Clean System Font Caches" (including the Microsoft cache). After doing
so, it prompted a restart and I was completely amazed to find that I could open both kinds of documents.
I'm positive this was the issue for me. I tried so many other things and nothing worked until I did this. I'll be using it over the next few days and provide any updates, if something behaves badly again.
Thank you.