On needing to install a new PowerPoint theme, downloaded from the web, I found these useful instructions in the help menu.
- Save the template to /Users/username/Library/Application Support/Microsoft/Office/User Templates/My Themes.
- Restart your Mac.
You have selected a different option. Please restart you computer for the changes to take effect
Of course I ignored this instruction, and just closed PowerPoint. When reopened, PowerPoint found the theme and I was able to use it without a problem.
Now I wait for my Mac to explode. I’m sure PowerPoint Help is upset I didn’t restart the computer and wants to take revenge somehow.