Are they using Windows PCs or Macs? The problem is when you put Powerpoint in this mode it expects you to have a projector or 2nd screen of some kind connected. If you are using a computer with a single screen there is going to be a problem.
Its on a mac notebook (but this problem is also on windows)
Workspace with second Monitor is working fine (Mac + Win). Only one screen laptop is showing white screen.
Thank you. Unfortunately, if you have a single screen there is no way to use Presenter mode and share the Slideshow. In similar screen sharing situations in the past it was possible to trick the computer into thinking a display was connected by just connecting a cable, but that is not working with the current MacBooks.
I haven't fully tested this, but this seems promising: https://support.microsoft.com/en-us/office/start-the-presentation-and-see-your-notes-in-presenter-vi...