I got this info for you from the owner`s manual;
To access a DVR or restricted menu, you should have logged in to
If you start the system or try to access restricted menus, the login
dialog pops up.
Double-click any area on the screen or press the [ENTER] button on the
front panel to display the virtual keyboard. (Page 26)
Select a user and enter the password.
The default admin password XXXXX "4321".
If you have successfully logged in, the Live screen appears.
The default screen is in 4-split mode with an option of continuous recording.
I know that you`ve tried it but somewhere perhaps you missed something.
This info was on page 17 of the user manual that you can download here;
Try it and let me know.