I have a 2009 macbook running El Capitan. If I plug a pen drive into my mac and read something.. pdf or word file etc then close the file and eject the drive without editing the file this is. If I then plug it into windows I get a pop up that says this drive needs to be checked. So I check it and open the same file but now it is corrupt! plug back into my mac and it works! I have had to copy files using my mac to our server at work then copy to the stick again from server on the windows machine! Any ideas why it is not working in windows after my mac has read it? ran malwarebytes just to check. nothing. getting annoying as usb pen stick at work between machines.