You're using the H.265 HEVC encoder which is very new, and I wonder if you'd still have the issues if you produced to the same profile in H.264 AVC [MPEG-4 1280x720 24p (16Mbps)]
I have no trouble importing, playing or editing the clip here on my Win10 desktop, so I'm really starting to think that the reason your friends can't play it is because their PCs can't play HEVC videos. Even though you're producing to "MP4" it's the codec you're using that matters and I'd be very surprised if you or your friends had any problems with the H.264 settings I listed above.
Please try producing to that and see how it goes. When you get a chance, please run the DxDiag test and attach the results for your desktop. It will still be helpful to see what's going on there.
YouTube/optodata
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