Twice today Windows did an automatic update on my brand new PC.
If you right-click on the desktop/displaysettings/fonts,etc. you can set up the way you want your fonts, menus and icons, etc. to look.
When Windows updates it pushes these settings back to default.
Also, when Excel is loaded, it will close down Excel, and create a new file called whatever.xlsx(repaired), which is a super annoying pain.
For that reason I've yet to install Office on my new PC. I still use the old one for that.
So I did some digging and
I found this site (scroll down about half-way), which tells you how to disable the automatic Windows updates.
Just remember to reverse the process and turn them back on occasionally to get new updates when it is convenient for YOU.