Ricoh Aficio MP 161SPF - Manual (Page 157)

Authentication Information
149
7
L
Select the function you want to set the user code for using {V}, 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.
Note
❒ You can enter a one-to eight-digit user code.
❒ For registration of a name, see "Registering Names".
Reference
p.140 “Registering Names”