Why does Dropbox remove a file from my hard drive when I "back up" to dropbox? The "dropbox help" info does not explain this. I've selected the option to "keep copies on my hard drive", but files still vaporize off my hard drive as soon as I copy them to dropbox. Do I need to turn off synching? I didn't mean to turn it on in the first place, and now it seems it seems I've inadvertently given dropbox permission to mess with my computer such that if I change any settings or if I unsynch a folder/file, it will disappear off dropbox AND OFF MY HARD DRIVE. I guess I don't understand Dropbox at all. But what does Dropbox not understand about the concept of a "BACK-UP"? A back-up is a copy, not a replacement. I don't want synching across devices etc. I just want a few files backed up to the cloud, and for the original FILES ON MY COMPUTER TO BE LEFT ALONE PLEASE. The help info is totally unhelpful on this. Can anyone tell me how to do this without losing files?