in the module:  Extend Your Reporting Strategy with AppExchange.  I launched my trailhead, went to settings, opened app exchange, picked an app, selected "get it now", then was presented with screen saying I needed to log in.  I clicked something like "open log-in screen" and get a spinning wheel.  Have tried different scenarios of this, inluding opening in new tab, but nothing works.  I may get a log-in opportunity by opening in new tab, but when I do, it doesn't recognize my login credentials.  I click "reset password" and it never emails me.

I'm getting the following error when Checking the challenge for the Enable Salesforce Knowledge component of the Knowledge Basics module in Trailhead even though everything is set up correctly according to the article. Knowledge is enabled, the language is set and the user has the appropriate permission. What am I missing?