AASTRA DT4x2 for BusinessPhone User Guide EN - Manual (Page 70)

Security
BusinessPhone – Cordless DT412/DT422/DT432 70
Block extension
æ
Press.
*72#
Dial to block your extension.
Verification tone.
Un-block extension æ
Press.
#72*
Dial.
å
Dial your Password.
#
Press to re-open.
Verification tone. Your extension is open for use.
Lock the keypad
You can lock your keypad to avoid accidental activation or dialling a
number by mistake. The following procedure describes the manual
lock, but it is recommended to always have the automatic lock on.
How to set the automatic key lock, see section “ Automatic key
lock ” on page 101.
Lock/Unlock the keypad manually ç *
Press to lock/unlock the keypad.
The Key icon indicates that your keypad is locked.