I'm certain I've done it before but perhaps not on my Win 7 desktop.
When I finished copying a cluster of jpg files from my SD card to my desktop I attempted to delete that same group of tagged files.
Ztree error: Write Protected [19]
Using Explorer I selected that same group, then right click for a menu -- delete was not one of my options.
When I removed the card I checked the tiny slider protection switch and it was not in the Lock position.
I guess I'll have to learn how to manage my photo files on the camera unless ya'll can give me a clue to what I'm missing here.
Len