Could not load file or assembly 'Python.Runtime' error

Hi @mahagh, my best guess of the source of the issue is there is another plugin you installed that uses another version of Python.Runtime, which creates a conflict with the Pollination plugin.

What version of Rhino 8 do you have installed? You can use SystemInfo in Rhino command to get the full details.

Please zip this log folder and share it with us for debugging.
%appdata%/pollination/logs