To do a master clear or master reset if I remember correctly on the ZN4 you need to turn the option on in SEEM 2742 offset 9F bits 1,2,7. This won't help though as you will get the menu in settings but if you cant get past the lock code you won't get there. If you don't care about what is on the phone just flash it with the monster, if you do care then use this with RSD Lite and your lock code will now be 1234:

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