Ricoh Aficio ISC 615G - Manual (Page 267)

Registering a Protection Code
259
7
J
Select [Destination Only ], [Sender Only] or [Dest. & Sender] using {U} or {T}, and
then press the {OK} key.
K
Select [Dest.Protect Code] using {U} or {T}, and then press the {OK} key.
L
Enter a protection code using the number keys, and then press the {OK}
key.
M
Press the {Escape} key.
N
Press [End].
O
Press the {OK} key.
P
Press the {User Tools/Counter} key.