Hello!
I had the same issue.
Here's what I followed to fix my issue: https://myinnerpc.zendesk.com/hc/en-us/articles/360042173231-How-to-Revert-Office-365-to-a-Previous-...
When you write your "config.xml", make sure to type 15831.20208 instead of the numbers the article has. I attached a screenshot here so you can see how I typed mine.
You only have to update it once. You don't need to update it again after rebooting your computer.
I hope this helps!!
