I'm new to mac and recently got a new macbook pro. Over the weekend I was using it to copy files onto my USB stick. The files were about 650MB each. Everytime I try the transferring file dialog box appears and it either starts and freezes at some point during the transfer or freezes instantly. The stop transfer button appears to do nothing. Sometimes even force quit doesn't do anything. Is this a common problem or something I don't know about? The USB stick is connect via the USB port on my apple keyboard. Thanks in advance for your advice.