Hello,
I have Windows Server 2016 which is dedicated to Terminal Services. Every day +20 users logs in to it remotely and does all kind of work remotely. Only fixes I found in the internet for the problem I'm going to describeare for the Server 2008/2012.
Recently, on rare occasions, from time to time, one random user on the Windows Server 2016 cannot login. His login gets stuck in infinite log in screen loop. Now, as I said before, it happens very rarely – I'd say once or twice in a week on +20 daily logging in and working users on the server. It wouldn't be the problem if I could fix this problem but the only real FIX I found out is server restart/reboot/reset (I'll fill you on more details as you read further in). To escalate the problem further this is production environment server – I cannot restart server as I please (also it annoys users a lot, I must call each user individually and inform them about server reboot – not an easy task for me because I also have the tight schedule). Biggest problem is that this issue can occur let's say at the start of the work day (what happened today) for one user so I cannot wait till the working hours ends – I must "organize" the server reboot (call every user and inform them about it).
This problem starts innocently: user gets stuck in infinite Login screen. User calls to IT help desk that he/she cannot login. IT staff opens Task Manager in the server. Here the things start to get interesting: problematic user login name in "Users" tab of the Task Manager is not visible. Instead Blank user (no username – just blank space) with 4 processes are seen. If I see that user (BLANK) I know that I have problem without fix (unless you count server reboot). Now if I try smart approach I can try to force disconnect/logoff stuck user, so he can try to re-login and/or force quit stuck processes (user can try to login to the server freshly because he has no processes running on the server).
However, if I disconnect blank user through the console (I can try to "Sign Off" user from the Task Manager – does not work) he can never login back to the terminal server – user reconnects and sees error "The task you are trying to do can't be completed because Remote Desktop Services is currently busy" after acknowledgment of the error users gets disconnected and if he reconnects he sees same error. IF I kill all processes of that session in the server (with the help of tasklist, taskkill /PID XXX /t /f) and the user reconnects to the server he gets the message “Please Wait for The User Profile Service”. This message never disappears – tried to wait 30 minutes. In this state user session cannot be logged off – if we try to open Task Manager “Users” tab we will see BLANK user session (I guess you already can see LOOP pattern in this).
What else? Server resources is not the problem, no updates were installed or pending to install (server needed to be rebooted).
Any suggestions will be appreciated. However I'll cannot apply them very often/fast (unless its related to the currently running server configuration) because the Issue appears once a week at max.