Permission problems with image

Trevor, what file types is your GM trying to upload?

Are you the only player experiencing the problem?

My guess is the GM deleted the image from his library. That's pretty much the only thing that causes Permission Denied errors. His computer may still have it cached locally so it is working for him but no one else. You might mention that to him and see what he says. If that doesn't ring a bell have him post here with the details of what he uploaded and we'll take it from there.