Hi,
On the server side, you can check below event logs and focus on the logs at the issue time.
Event Viewer – Applications and Services Logs – Microsoft – Windows-remoteapp and desktop connections
Event Viewer – Applications and Services Logs – Microsoft – Windows – RemoteDesktopServices-****
Event Viewer – Applications and Services Logs – Microsoft – Windows - TerminalServices-LocalSessionManager
Event Viewer – Applications and Services Logs – Microsoft – Windows - TerminalServices-RemoteConnectionManager
But, we suggest that you should share the error message you got when the user failed to log onto the terminal server, so that we can proceed further investigation.
Thnanks,
Eleven
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