Sorry its not clear, What you meant by exchanging files?
In pro version, to give access to different user different files
One way is , create a package ( Downloads Add New ) for one user add all that user files and apply password lock from Lock Option in Package Settings metabox. So when a user comes to that page he will need to enter password to download files.
Another Way is. if users are under a user role. then you can create one for more packages for them and from Access field simply need to select the user role you want to give access to that package.
But let me know if you still not clear.
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