The system requires that you sign on to a valid account. The error code is: 0xD000000C on Microsoft Office for Mac Activation
Issue
When starting Microsoft Office products for the first time, you get a popup window asking you to Activate your software.
When you enter your credentials your receive the following message :
The system requires that you sign on to a valid account. The error code is: 0xD000000C
Solutions
Close all Microsoft Office apps
Microsoft License Removal Tool
Download and Run Microsoft License Removal Tool from the following link
https://go.microsoft.com/fwlink/?linkid=849815
Uninstall Microsoft Office and Cleanup preferences files and folders
You could use this script :
https://gist.github.com/pirafrank/18d62c062e2806c1d183#file-uninstall_office_2016-sh
Delete all Office entries from the Keychain app
This should have been done by the Removal Tool (check above), but it’s better to check twice.
Search for “office” (I also did the same for “Microsoft”, and “Exchange” cause I’m crazy enough) and delete the entries (make a backup if you would like ๐ ).
Install and activate from a local account
There is apparently an issue when activating Microsoft Office from a Network account. If you don’t have a local account, create one and reinstall Microsoft Office from it.
Try to activate and try again (that one for the desperate)
Check this article ๐ :
TLDR :
Then, for probably the 25th time in a day, I tried launching Word. And what do you know? I didn’t get the error message. I got an actual prompt to login. I typed in my user name and my password and, as if by magic, I was once again able to use Office.