xcopy "copies only files that don't already exist on destination"

Question

Does anyone know how to do this?

I can copy only files that DO exist on the destination, but not the other way around... any ideas?

More information

• I have 3 gigs of files on System A.
• I have 4 gigs of files on System B.
• Many of the files are the same
• I only want to copy the files from System B to System A that don't already exist on system A.

Thanks!

Answer 1

If it's Vista, you can use RoboCopy and exclude (/XF) that is matching.

To see all option go in cmd.exe and type robocopy /?

Answer 2

You can also try to use RoboCopy's mirror feature instead? Handles folder as well.

see http://www.lukemiller.org/journal/2007/08/mirror-files-with-robocopy.html

//Andy

Answer 3

You may want to give robocopy a shot. Don't worry, its already installed on Vista and Server 2008 and its free for XP and Server 2003. There is a sync mode that will keep directories in sync

There's also a GUI for it.

Answer 4

Old fashioned? Try this:

C:\>xcopy c:\temp\testcopy\source c:\temp\testcopy\target /e /d

It will copy the files that don't exist on the target. It will also copy the files that are newer on the source than the target.

Answer 5

Just use /XN /XO to ignore newer or older files and it will just copy files which dont exist already, simple!