More information: I found the AppDynamics logs, and this was found in the WarnLog.txt file:
2019-07-31 22:17:59.6405 11564 w3wp 2 9 Warn ConfigurationChannel Could not connect to the controller/invalid response from controller, cannot get initialization information, controller host [earhart2019073008060724.saas.appdynamics.com], port[443], exception [System.Net.WebException: The remote server returned an error: (401) Unauthorized.
So maybe I have something wrong in my configuration. I found a file called usercacheconfig.xml that had incorrect values for my account name and account key, so I changed them in there and restarted. Now the error I get is:
2019-07-31 22:30:28.1610 10028 AppDynamics.Coordinator 1 5 Warn RegistrationChannel Could not connect to the controller/invalid response from controller, cannot get registration information
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