Have just wasted a lot of time trying to figure out how to connect Hubshare to a vault. The user guide is not very clear in how you need to specify the URLs.
I finally figured out that you need to put the REST API URL (which is also the Classic Web URL) in the place for Server URL and the Web URL in the gRPC domain. In my case the Classic Web URL is in a Classic subfolder. That may not be the case elsewhere. The important thing is to place the correct URL in each field as shown below.
Hope this can save somebody some time in the future. It really should be included in the Guide!