Help Copying videos from PC without being asked "Do you want to copy it? You might not be able to view it

[cdl]

I have a Sony Z5 running Nougat and a Windows 7 PC, but I am posting this here because I understand it's a general point which affects most phones.

How can I get rid of the annoying message

"Do you want to copy file XYZ?
No
Yes: Your file will be copied, but you might not be able to view it"

which appears every time I try to copy a video file (which the phone then plays perfectly fine) from my PC to my phone?

Thanks!