This is a very quick post to help some people out on installation problems with Office for Mac 2016.
On excited installation of Excel 2016 on my Macbook, the following error threatened to ruin the day:
“An unknown error has occurred, the error code is: 0xD0000006”
Seemingly unfound on the internet, the solution, oddly enough was to ensure that the “name” of the computer has no special characters. The Macbook in question had an “á” in the Computer name.
To change the name of your computer, open up “System Preferences” by pressing Command-Space and typing “Preferences”. Alternatively, click your Apple symbol on top left and click “Preferences”.
Under the “Sharing” option, you’ll find your computer name.
Hope this helps out.

System Preferences on Macbook Pro.

Sharing options on Macbook Pro