I have a 250 gb usb 2.0 Lacie External. I've never emptied the trash on it, and when i go to do it, it says its deleting like 5 or 6,000 files. While its entirely possible that I have added/removed that many files ocver the past year, Im worried its gonna wipe out my drive. How can I lock my 5 main folders to secure them from being erased???