Locate the model/brand on the lock or door label
Search the manufacturer’s website for the specific reset/unlock instructions
Try the factory default code (common examples: 0000, 1234, 9999) only if the lock is new/known
If you know the code but forgot it, check your owner manual, notes, or prior records
If it has a reset function, use the manufacturer’s reset procedure to set a new code
If it has a key override, use the key if you have authorization
If it’s a padlock with a shackle, contact the manufacturer for authorized service options
Contact a licensed locksmith for non-destructive entry if you can prove ownership/authorization
If it’s a rental or managed property, contact the property manager or landlord for access procedures
Avoid forcing the lock if it may damage the door, frame, or lock mechanism
If you cannot access proof of ownership/authorization, stop and request assistance from the appropriate authorized party