Environment Variable SNAP_HOME Windows 10- How to add?

[marpet]

And you followed also this guide?
https://senbox.atlassian.net/wiki/spaces/SNAP/pages/50855941/Configure+Python+to+use+the+SNAP-Python+snappy+interface

Just a note, not sure if it is mentioned in the guide you have linked.
After changing the environment variables you need to restart the windows command line or the python environment. The variables are only read when the process is started.

Maybe also these post might help you:

Issues installing snappy Can't find SNAP distribution directory. Ubuntu 16.04 LTS

in snappy.ini, snap_home should be set to the fullpath of the main SNAP directory, not the .snap user settings directory. More information would be helpful. You shouldn’t need anaconda python for snappy on Ubuntu 16.04. Did you install anaconda after having problems with the distro python2.7? Which version of SNAP do you have? Did you specify the path to anaconda python when you installed SNAP? This path is passed by the installer to snappy-conf, but you can also run snappy-conf in a ter…

How to assign the SNAP_HOME variable?

Is /home/user/snap the installation directory of SNAP? If so, it should be correct. Maybe you try to configure snappy again. Invoke snappy-conf.sh <python_executable> <site-packages_folder>. This could solve the problem.