First login to the Astaro firewall with a web browser and in the settings enable SSH.
From you client issue the command minus the quotes: "scp filename loginname@hostname[:D]estinationdirectory
For example if you were using Putty on a Windows station and copying the file test.tar to a host 192.168.0.1, and destination directory /home/test and a user name test your syntax would look like this:
pscp test.tar test@192.168.0.1:/home/test.
You would then get a message prompting you for the password for the user test.