HP BT400 User Manual page 9

When the printer's security level is set to "Low", the
printer does not require a Passkey code. Any Bluetooth
device may print to it.
● High
When the printer's security level is set to "High", you
must enter the Passkey code in the sending device in
order to print.
Passkey/PIN code
When the printer's Bluetooth security level is set to High,
the sending device attempting to print is prompted for a
Passkey. The Passkey is a 4-digit code that is set on the
printer. The default Passkey is 0000.
The following are general instructions for finding your
printer or all-in-one's Bluetooth passkey. Consult the
documentation for your printer or all-in-one for specific
instructions.
1. Access the control panel menu and select the
Bluetooth option.
2. Select Passkey and press OK to display the printer's
Passkey.
You can also change the Passkey from this menu.
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