Word 2016 for Mac Won't Open Docs - Cannot open global template - Microsoft Community
The below was found at answers.microsoft.com
Unfortunately, it seems that today images are all broken in the forum. Perhaps this problem will be resolved.
Meanwhile, from what I can gather, there is a problem with the normal template.
The normal template is simply a Word template that Word uses when it opens or makes a new, blank document.
Because I am lazy and I like to try easy things first, my first suggestion is to simply restart you Mac. Does that fix the problem?
If it does, we're done and can go have a nice party, or do the work we wanted to accomplish.
If that doesn't take care of the problem, Word will make a brand new, factory fresh template with new template smell if Word can't find an existing normal template to use. All you have to do is make sure you completely quit Word first, then either rename or move the existing normal template. When Word starts up, it will make that nice, new default template.
It's a bit of a chore to find your templates because Apple insisted Microsoft put them in a hidden location. Dumb idea? You bet! First, unhide the Library folder:
How to Show the User Library Folder in macOS Sierra - The Mac ...
Then, navigate to the User > Library folder that stores your templates. The directory is very intuitive (not!). Hopefully, this image will display for you:
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