Sorry about the issue. What version of the Pollination Rhino plugin are you using?
This is most likely a dependency conflict with another plugin that you have installed. Can you share the logs from this folder with us? %appdata%\pollination\logs. There will be many files, but we need the one for today when this error happened.
Can you try the PO_LicenseManagerClassic command instead? That should bring up the classic version of the license manager.