Overview
When the Office Timeline tab is missing from PowerPoint, a common cause is PowerPoint running in administrator mode.
One common cause is running PowerPoint with elevated (administrator) privileges.
Office Timeline is a per-user add-in and may not load correctly when PowerPoint is run as an administrator.
Solution
Ensure that PowerPoint is launched in standard (non-administrator) mode.
Running PowerPoint with elevated privileges can prevent Office Timeline from loading because it uses a different registry context than the one where the add-in is installed.
Steps
Close all open instances of PowerPoint.
Start PowerPoint normally:
Open PowerPoint from the Start menu or desktop shortcut
Do not right-click and select “Run as administrator”
If PowerPoint is configured to always run as administrator:
Right-click the PowerPoint shortcut or executable
Select Properties
Go to the Compatibility tab
Uncheck “Run this program as an administrator”
Click Apply, then OK
Open PowerPoint again and confirm that the Office Timeline tab appears in the ribbon.
Additional Notes
This is a known limitation of COM add-ins in elevated mode.