Hi @Rising Flight
Isn’t this option shown after right-click PowerPoint’s built-in theme?
Please go to C:Users\<UserName>\Documents\Custom Office Templates\Document Themes
, and %appdata%\Microsoft\Templates\Document Themes
check whether there is any theme file end with .thmx. If yes, please move it temporarily.
Besides, if the user put a custom template file (.potx, .potm files) in C:Users\<UserName>\Documents\Custom Office Templates
, please also move it somewhere else temporarily for a check.
Then please click File > Options > Add-ins > Manage COM Add-ins, click Go, clear the check boxes for any enabled COM add-ins, select OK. This action can help us troubleshoot the COM add-in.
Relaunch PowerPoint for a check.
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