> thanks for the hint. Anyway as much as I see it, Plasma Vault would be
> linked to my KDE, but I search for a solution to encrypt files or
> folders in a way that I can put them anywhere and share with others.
> 
> I am looking for something to encrypt files so that somebody can decrypt
> them even on a Mac or Win-PC. With this I could for example deliver
> private client photos via dropbox or similar.

I wonder if Veracrypt is the answer you are looking for.

You create a container (file) that you would mount as a volume/drive using a password (which is always required)

Then you copy files or directories into the mounted drive. Once you unmount the drive you can place that container 

anywhere. Anybody you wish can download the file and mount it using the password you send them.

It's cross-platform.

Payam F.