Hi @David George
Did you can open PowerPoint presentations or run PowerPoint properly?
Any error messages or error codes, please share with us.
Have you installed any updates to Office or Windows recently?
On June 11, both Office and Windows will have updates rolled out. KB5039212 is for Windows to update to Build 22631.3737. For Microsoft 365 Apps, such as Current Channel, the latest version is 2405 (Build 17628.20144)).
If updates were installed, it is recommended to temporarily roll back the version of Office and uninstall the Windows update.
Besides, I suggest you perform an Online-Repair for Office to have a check.
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