Windows 10: Copying files to a galaxy s9, skip duplicates

How can I update my downloaded fanfic library that I have sort of backed up to my Samsung Galaxy S9 phone? It's not intended as a backup, more like an offline sync.If I copy all the files in a folder where there are some duplicates on the computer, I get asked what to do with a file with "copy" or "don't copy".If I check the checkbox that says "do this with all" and click "don't copy", it immediately aborts the copy, not bothering to copy the files that are NOT duplicates. If the first duplicate encountered is a folder, I get asked if I want to replace those files. Clicking "no" immediately te

:)

 

Can no longer skip duplicate files on directory copy?

When I copy a directory from my phone to my Windows 10 laptop, I used to get two prompts: The first one would warn me that there was a FOLDER with the same name at the destination and ask me if I wanted to merge the source folder into the destination folder.
Then I would get a second prompt, warning me about duplicate FILES, which would ask me whether I wanted to replace or skip each duplicate file.

This behavior has changed. Now when I copy directories, I no longer get the second prompt. If I choose to merge the DIRECTORIES, it appears to be automatically overwrite duplicate FILES, even if I leave the "do this for other conflicts" block unchecked in
the directory dialog.

I have the "Hide folder merge conflicts" box UNCHECKED in folder options. (There does not seem to be a corresponding "Hide file merge conflicts" box.)

If I go into each directory and copy the files individually (without the parent directory), I DO see the "skip duplicate files" dialog.

It is cumbersome to have to go in and select 2,000 files in order to just weed out the news ones, but without it, a file copy that should take a few minutes takes TWO HOURS instead.

Why has this behavior changed, and how can I skip duplicate files when I copy a folder?

 

Is there a way to skip duplicate files when copying?

I have a 3TB external hard drive that I use to backup large files. Usually, I just drag and drop the folders from my laptop to the external drive and Windows gives me an option to skip duplicate files AFTER it copies the new files. That has been working fine but now I am getting an error saying that there is not enough space on my hard drive and it won't let me transfer. But I just want to copy the new files and skip the duplicates. I already know there is enough space for the new files. A way to work around this is to find each new file and copy them manually, but that takes a lot of time and I don't want to do that. Is there a way to have Windows automatically skip duplicate files BEFORE the transfer starts so that it won't count the space of the duplicate files?

 

Is there a way to skip duplicate files when copying?

Why not use an external program like FastCopy or FreeFileSync?