Xbox files corrupt on flashdrive when Put on Laptop? How to fix?

So I put a few downloaded maps onto my minecraft on the Xbox. My friends wanted me to get a few more and after transferring my profile and a world over to do it, a pop up comes up saying that the files were corrupt. Early this morning I did the same thing and it worked fine then a few hours later doing the same processes it won't.

Flashdrives that you've converted for the Xbox won't convert into your PC without the data being corrupt or deleted. It should ask you to convert your flashdrive and delete all the files in it once you put the flashdrive in the Xbox. If you're transferring the maps from your xbox to your friend's xbox then it should be fine. I don't quite understand why you'd use a PC for this, but that's all I know.