|How did you go about placing the files on the removable disc?|
What type of files are they?
I've found that sometimes drag and drop will create a shortcut, rather than copying the file over. From memory (not that reliable at my age), I came across this problem when trying to send JPEG files to a USB drive. It was quite some time ago that this occurred, and I've avoided drag and drop ever since. Nowadays, I always use copy/paste or cut/paste, unless the "Send To" option is available when right-clicking the file.
Check the size of each file on the removable disc. If they are relatively small files (around the 4KB mark) they will actually be shortcuts, not the actual files.
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