can't create ftp account - owncloud directory

[Slayer]

Hello!

I can't create a ftp-account with Plesk for a user owncloud directory.

I only can reach the directory /httpdocs/data/
When i try to create a account with a deeper directory, like /httpdocs/data/user/ or /httpdocs/data/user/files
this message appears: "The file or directory does not exist". But of course it exist.

If i change the home directory over a ssh client it works, but in plesk is displayed /httpdocs/data/ anyway.

I guess that plesk doesn't have the permission to do that. But how can i give plesk the permisson?

The OS is: Ubuntu 14.04 LTS 64bit + Plesk 12.0.18

Best regards,
Patrick