NEC DS2000 Feature Handbook page 105

3. Enter your current PIN number +
At a 22- or 34-Button Display Telephone, you see:
At a Super Display Telephone, you see:
4. Enter the number of the extension you want to unlock +
.
HOLD
At a 22- or 34-Button Display Telephone, you see:
At a Super Display Telephone, you see:
Extension Locking
.
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