How to avoid duplicate files

Question

When I copy the contents of a folder to a usb drive, I sometimes am given the options to keep both copies or to skip that (and any others like it) in the folder I am copying into. I keep video files in a video folder that is on a usb drive and I try to copy them from C/drive/videos as often as possible. However sometimes I am not sure of where I stopped copying the last time and select files already in the destination folder. Why don't I get the option to skip if a duplicate consistently? Is there a way to prevent duplicate files when doing this?

Answer 1

What type of USB drive are you using? I use an external 500gb USB hard-drive and cannot replicate your issue, but mine is (pretty much) permanently connected.

I always manage items I am copying over in folders, so when I add new files they get copied to the external drive in a folder. If I do inadvertently duplicate something the only place it is likely to be is in the previously copied folder, and it is a simple matter to check.

One other point, when you have copied items to the external drive are you still retaining the files on the main drive or are you deleting them?  - Thanks - R.