Did you check event viewer ?
Please read the following link for more details: Please wait for the System Event Notification Service
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Hi, When user logout a server, it will show "Please wait for System Event Notification Services". It needs to wait 1-2mins to logout. This problem happened on any user. We check the process chain of winlogon.exe but it don't have any processes already. How can we trace which services hold the SEN services?