QNAP Security NVR-101 (Version: 2.8.0) - Manual (Page 64)

5.5.2 Edit User
Select a user on the list and click Edit. You can change the password, assign
system administration and camera access control. However, the user name cannot
be changed.
5.5.3 Delete User
To delete a user, select a user on the list and click Delete.
Click OK to confirm.
Note: System administrator cannot be deleted.
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