Can you clear the Locknetics PRO 79 of all user codes?

Yes.
Memory may be erased to conveniently return to default 
1. Disconnect power.
2. Press any button one time.
3. Reapply power. Red and green LEDs flash alternately.
4. Press * key 3 times quickly immediately after LEDs stop flashing. Red and green LEDs flash alternately.
All programmed codes will be erased. Factory default codes and time settings will be restored.

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