WebUI Uninstall/Reinstall, Best Practice

I just installed it yesterday and I am getting this issue:

Or, at least, a variant of it. We are on 9.5.9 and have very few devices so far, so after manually removing entries from the database and removing the sites from the /webui folder on the server, we are just blowing it away since we have basically done nothing in WebUI yet.

Sorry I’m not much help!