This article describes the issue – Windows 10 1903 feature upgrade removes the already installed client connector and breaks the Essentials features such as client backup, Remote Web Access, LaunchPa...
Updated Jun 27, 2019
Version 3.0
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We couldn't reinstall the connector either.
Reinstalling was the usual goto when MS bricked the connector with an update. However, we kept getting an error when trying to select the server to connect to in the wizard, "Cannot get information from (IP) please contact your system admin" or "No server detected in the network".
Try the connector available through the remote web access page of your server. HTTPS://servername.remotewebaccess.com/connect.
I connected to the machines as a local admin and ran it which seemed to work.
On the first machine, I took the machine off the domain and rejoined but on the second I didn't bother and it's fixed both.
I can't explain how this is any different but it worked for us.
It seems to skip the "select the server in the drop-down list" part of the wizard that our machines were getting stuck on.