Won't let me embed a video even though it did earlier?

I’m making a rotoscope animation through photoshop for class, we had to animate over a video we made. I used one of the class-owned macbooks and it let me embed a video no problem, now I’m trying to finish it as homework and I’m using my windows laptop, it said it couldn’t find the video I had embedded so I tried re-adding it and all it does is say “Could not complete your request as the footage is not a recognised format”. It’s an MP4, I tried converting it to an AVI and that didn’t work either. I have no idea what to do? Everything is updated, it just really doesn’t want to embed the video.