I have multiple memory sticks that I use for work. In all cases when I try to delete files from the stick on my Mac it says they are gone but the disk is still full. I have to take the sticks home, plug them into my windows machine, and delete them there to actually remove them. I can't reformat the disk every time I try to delete a file because there are a lot of files left on the memory sticks that I need to keep. Is there a trick to deleting files on a Mac? Seems like if I chose to delete a file it should just go away. I'm very frustrated with Apple anyway and this doesn't help.