in response to mark's answer-ER-5100?

Ok Mike. Next we try an initial reset.
This will tell the machine to stop what it is doing, and allow us access without losing data.

Turn key to P mode.
Turn power off at the wall.
Hold SUBTOTAL button down. Keep your finger on it.
Turn power on at wall, and wait for printer to run, then let go of SUBTOTAL.

Leave key in P mode.
Press CASH
Press SUBTOTAL

If it works, you should get a list printed showing the programming. Look for 'CLK1 CODE' on the list. The number next to it is your logon code.
Go back to REG mode, and try that clerk code to logon.

Mark
October 2008