Even if you are a domain admin in your environment you cannot log off other users from their computers in the task manager, you should run the task manager processes in an elevated mode, follow these simple steps:
- Open Task Manager (taskmgr.exe) and click the Processes tab
- Click Show processes from all users
- When you are prompted for an administrator password or confirmation, type the password or provide confirmation.
(Task Manager now runs with administrative privileges.)
- Switch to the Users tab and log off an user account.
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