Turn the oven control knob to the "Off" position to interrupt a cleaning cycle in progress. Wait at least one hour for the oven to cool, which releases the thermal lock.
Pull the lock lever above the oven door to the left to unlock the door. If the lever still will not open after the cool-down period, continue troubleshooting.
Cut off the power to the Kenmore at the circuit breaker and wait 10 minutes before restoring the electricity. This resets the electronic controls to factory defaults and may release the locking mechanism if the oven has cooled. If the lock lever will not release after all troubleshooting attempts, contact a repair technician.