why did my powerpoint presentation via a projector suddenly stop showing what was on the laptop scre

[Judecc]

I was running a presentation today when halfway through instead of showing the next slide, which was displayed on my laptop screen it switched to projecting my desktop!



I tried restarting powerpoint and re-starting the slide show but the projector refused to show anything except the desktop.

I also tried other applications which displayed on the laptop but same problem.

Can anyone help, as I have another presentation to do on Friday?

Thanks. Jude