Yes, I would recommend disabling and then uninstalling the jibo SDK package followed by reinstalling to get version 1.7.1.
When you are updated to that version I would recommend running
npm install in the directory for your skill where you are using SubtreeJS.
If you continue to see this error I would recommend doing a test of using SubtreeJS in a project created after updating to 1.7.1. If it works there but not in your existing project there may be some steps I can recommend. I would also recommend making sure you meet all of the system requirements/decencies seen here.
Lastly, it is worth noting that there is a possibility that there is something about Windows 7 that might be causing the issue. We have seen some versions of the SDK work on that operating system but as noted in our requirements the SDK is not guaranteed to work on anything below Windows 8.
Let me know if the above clears up the error you are seeing and, if it does not, I will do everything I can to recommend further steps keeping in mind that that there may be a limit to what I can recommend with the SDK running on Windows 7.
Thank you again,